text:
, Todd and Skrutskie, Michael F. and Walker, Eric and Wilson, John C. and Zasowski, Gail and Anders, Friedrich and Basu, Sarbani and Beland, Stephane and Blanton, Michael R. and Bovy, Jo and Brownstein, Joel R. and Carlberg, Joleen and Chaplin, William and Chiappini, Cristina and Eisenstein, Daniel J. and Elsworth, Yvonne and Feuillet, Diane and Fleming, Scott W. and {Galbraith-Frew}, Jessica and Garc{\'i}a, Rafael A. and {Garc{\'i}a-Hern{\'a}ndez}, D. An{\'i}bal and Gillespie, Bruce A. and Girardi, L{\'e}o and Gunn, James E. and Hasselquist, Sten and Hayden, Michael R. and Hekker, Saskia and Ivans, Inese and Kinemuchi, Karen and Klaene, Mark and Mahadevan, Suvrath and Mathur, Savita and Mosser, Beno{\^i}t and Muna, Demitri and Munn, Jeffrey A. and Nichol, Robert C. and O'Connell, Robert W. and Parejko, John K. and Robin, A. C. and {Rocha-Pinto}, Helio and Schultheis, Matthias and Serenelli, Aldo M. and Shane, Neville and Silva Aguirre, Victor and Sobeck, Jennifer S. and Thompson, Benjamin and Troup, Nicholas W. and Weinberg, David H. and Zamora, Olga},
  year = {2017},
  month = sep,
  volume = {154},
  pages = {94},
  issn = {0004-6256},
  doi = {10.3847/1538-3881/aa784d},
  abstract = {The Apache Point Observatory Galactic Evolution Experiment (APOGEE), one of the programs in the Sloan Digital Sky Survey III (SDSS-III), has now completed its systematic, homogeneous spectroscopic survey sampling all major populations of the Milky Way. After a three-year observing campaign on the Sloan 2.5 m Telescope, APOGEE has collected a half million high-resolution (R \texttildelow{} 22,500), high signal-to-noise ratio ({$>$}100), infrared (1.51-1.70 {$\mu$}m) spectra for 146,000 stars,
with time series information via repeat visits to most of these stars. This paper describes the motivations for the survey and its overall design\textemdash hardware, field placement, target selection,
operations\textemdash and gives an overview of these aspects as well as the data reduction, analysis, and products. An index is also given to the complement of technical papers that describe various critical survey components in detail. Finally, we discuss the achieved survey
performance and illustrate the variety of potential uses of the data products by way of a number of science demonstrations, which span from time series analysis of stellar spectral variations and radial velocity variations from stellar companions, to spatial maps of kinematics, metallicity, and abundance patterns across the Galaxy and as a function of age, to new views of the interstellar medium, the chemistry of star clusters, and the discovery of rare stellar species. As part of SDSS-III Data Release 12 and later releases, all of the APOGEE data products are publicly available.},
  file = {/Users/Oliver/Zotero/storage/973SITQ8/Majewski et al. - 2017 - The Apache Point Observatory Galactic Evolution Ex.pdf},
  journal = {The Astronomical Journal},
  keywords = {Galaxy: abundances,Galaxy: evolution,Galaxy: formation,Galaxy: kinematics and dynamics,Galaxy: stellar content,Galaxy: structure}
}

@article{mamajek+2015,
  title = {{{IAU}} 2015 {{Resolution B2}} on {{Recommended Zero Points}} for the {{Absolute}} and {{Apparent Bolometric Magnitude Scales}}},
  author = {Mamajek, E. E. and Torres, G. and Prsa, A. and Harmanec, P. and Asplund, M. and Bennett, P. D. and Capitaine, N. and {Christensen-Dalsgaard}, J. and Depagne, E. and Folkner, W. M. and Haberreiter, M. and Hekker, S. and Hilton, J. L. and Kostov, V. and Kurtz, D. W. and Laskar, J. and Mason, B. D. and Milone, E. F. and Montgomery, M. M. and Richards, M. T. and Schou, J. and Stewart, S. G.},
  year = {2015},
  month = oct,
  pages = {arXiv:1510.06262},
  abstract = {The XXIXth IAU General Assembly in Honolulu adopted IAU 2015 Resolution B2 on recommended zero points for the absolute and apparent bolometric magnitude scales. The resolution was proposed by the IAU Inter-Division A-G Working Group on Nominal Units for Stellar and Planetary Astronomy after consulting with a broad spectrum of researchers from the astronomical community. Resolution B2 resolves the long-standing absence of an internationally-adopted zero point for the absolute and apparent bolometric magnitude scales. Resolution B2 defines the zero point of the absolute bolometric magnitude scale such that a radiation source with \$M\_\{\textbackslash rm Bol\}\$ = 0 has luminosity L\$\_\{\textbackslash circ\}\$ = 3.0128e28 W. The zero point of the apparent bolometric magnitude scale (\$m\_\{\textbackslash rm Bol\}\$ = 0) corresponds to irradiance \$f\_\{\textbackslash circ\}\$ = 2.518021002e-8 W/m\$\^2\$. The zero points were chosen so that the nominal solar luminosity (3.828e26 W) adopted by IAU 2015 Resolution B3 corresponds approximately to \$M\_\{\textbackslash rm Bol\}\$(Sun) = 4.74, the value most commonly adopted in recent literature. The nominal total solar irradiance (1361 W/m\$\^2\$) adopted in IAU 2015 Resolution B3 corresponds approximately to apparent bolometric magnitude \$m\_\{\textbackslash rm bol\}\$(Sun) = -26.832. Implicit in the IAU 2015 Resolution B2 definition of the apparent bolometric magnitude scale is an exact definition for the parsec (648000/\$\textbackslash pi\$ au) based on the IAU 2012 Resolution B2 definition of the astronomical unit.},
  file = {/Users/Oliver/Zotero/storage/KD37NLQ5/Mamajek et al. - 2015 - IAU 2015 Resolution B2 on Recommended Zero Points .pdf;/Users/Oliver/Zotero/storage/C5L3YVB6/ui.adsabs.harvard.edu.html},
  journal = {ArXiv e-prints},
  language = {en}
}

@article{mamajek+hillenbrand2008,
  title = {Improved {{Age Estimation}} for {{Solar}}-{{Type Dwarfs Using Activity}}-{{Rotation Diagnostics}}},
  author = {Mamajek, Eric E. and Hillenbrand, Lynne A.},
  year = {2008},
  month = nov,
  volume = {687},
  pages = {1264},
  doi = {10.1086/591785},
  abstract = {While the strong anticorrelation between chromospheric activity and age has led to the common use of the Ca II H and K emission index (R\textsuperscript{'}\textsubscript{HK} = L\textsubscript{HK}/L\textsubscript{bol}) as an empirical age estimator for solar-type dwarfs, existing activity-age relations produce implausible ages at both high and low activity levels. We have compiled R\textsuperscript{'}\textsubscript{HK} data from the literature for young stellar clusters, richly populating for the first time the young end of the activity-age relation. Combining the cluster activity data with modern cluster age estimates and analyzing the color dependence of the chromospheric activity age index, we derive an improved activity-age calibration for F7-K2 dwarfs (0.5 mag \< B - V \< 0.9 mag ). We also present a more fundamentally motivated activity-age calibration that relies on conversion of R\textsuperscript{'}\textsubscript{HK} values through the Rossby number to rotation periods and then makes use of improved gyrochronology relations. We demonstrate that our new activity-age calibration has typical age precision of \textasciitilde 0.2 dex for normal solar-type dwarfs aged between the Hyades and the Sun (\textasciitilde 0.6-4.5 Gyr). Inferring ages through activity-rotation-age relations accounts for some color-dependent effects and systematically improves the age estimates (albeit only slightly). We demonstrate that coronal activity as measured through the fractional X-ray luminosity (R\textsubscript{X} = L\textsubscript{X}/L\textsubscript{bol}) has nearly the same age- and rotation-inferring capability as chromospheric activity measured through R\textsuperscript{'}\textsubscript{HK}. As a first application of our calibrations, we provide new activity-derived age estimates for a volume-limited sample of the 108 solar-type field dwarfs within 16 pc.},
  file = {/Users/Oliver/Zotero/storage/IPJRXLI8/Mamajek and Hillenbrand - 2008 - Improved Age Estimation for Solar-Type Dwarfs Usin.pdf;/Users/Oliver/Zotero/storage/RHLQCMDK/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal},
  keywords = {Core Gyrochronology},
  language = {en},
  number = {2}
}

@article{mandel+agol2002,
  title = {Analytic {{Light Curves}} for {{Planetary Transit Searches}}},
  author = {Mandel, Kaisey and Agol, Eric},
  year = {2002},
  month = dec,
  volume = {580},
  pages = {L171-L175},
  issn = {0004-637X},
  doi = {10.1086/345520},
  abstract = {We present exact analytic formulae for the eclipse of a star described by quadratic or nonlinear limb darkening. In the limit that the planet radius is less than a tenth of the stellar radius, we show that the exact light curve can be well approximated by assuming the region of the star blocked by the planet has constant surface brightness. We apply these results to the Hubble Space Telescope observations of HD 209458, showing that the ratio of the planetary to stellar radii is
0.1207+/-0.0003. These formulae give a fast and accurate means of computing light curves using limb-darkening coefficients from model atmospheres that should aid in the detection, simulation, and parameter fitting of planetary transits.},
  file = {/Users/Oliver/Zotero/storage/XNDPQE9T/Mandel and Agol - 2002 - Analytic Light Curves for Planetary Transit Search.pdf},
  journal = {The Astrophysical Journal Letters},
  keywords = {C3}
}

@article{marti+2016,
  title = {{{ESASky}}: {{The}} Whole of Space {{Astronomy}} at Your Fingertips},
  shorttitle = {{{ESASky}}},
  author = {Mart{\'i}, Bel{\'e}n L{\'o}pez and Mer{\'i}n, Bruno and Giordano, Fabrizio and Baines, Deborah and Racero, Elena and Salgado, Jes{\'u}s and Sarmiento, Mar{\'i}a Henar and Guti{\'e}rrez, Ra{\'u}l and {de Teodoro}, Pilar and Gonz{\'a}lez, Juan and Segovia, Juan Carlos and Nieto, Sara and Norman, Henrik and Arviset, Christophe},
  year = {2016},
  month = oct,
  abstract = {ESASky is a new science-driven discovery portal for all ESA astronomical missions that gives users worldwide a simplified access to high-level science-ready products from ESA and other data providers. The tool features a sky exploration interface and a single/multiple target interface, and it requires no prior knowledge of specific details of each mission. Users can explore the sky in multiple wavelengths, quickly see the data available for their targets, and retrieve the relevant products, with just a few clicks. The first version of the tool, released in May 2016, provides access to imaging data and a number of catalogues. Future releases will enable retrieval of spectroscopic data and will incorporate futures to allow time-domain exploration and the study of Solar System objects.},
  archivePrefix = {arXiv},
  eprint = {1610.09826},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/ETHNE4T3/Martí et al. - 2016 - ESASky The whole of space Astronomy at your finge.pdf;/Users/Oliver/Zotero/storage/IAE3W29F/1610.html},
  journal = {arXiv:1610.09826 [astro-ph]},
  keywords = {Astrophysics - Instrumentation and Methods for Astrophysics},
  primaryClass = {astro-ph}
}

@article{masseron+hawkins2017,
  title = {The Spectroscopic Indistinguishability of Red Giant Branch and Red Clump Stars},
  author = {Masseron, Thomas and Hawkins, Keith},
  year = {2017},
  volume = {597},
  pages = {L3},
  file = {/Users/Oliver/Zotero/storage/THGA752R/1612.05061v1.pdf},
  journal = {Astronomy \& Astrophysics}
}

@article{masson2011,
  title = {A Tutorial on a Practical {{Bayesian}} Alternative to Null-Hypothesis Significance Testing},
  author = {Masson, Michael E. J.},
  year = {2011},
  month = sep,
  volume = {43},
  pages = {679--690},
  issn = {1554-3528},
  doi = {10.3758/s13428-010-0049-5},
  abstract = {Null-hypothesis significance testing remains the standard inferential tool in cognitive science despite its serious disadvantages. Primary among these is the fact that the resulting probability value does not tell the researcher what he or she usually wants to know: How probable is a hypothesis, given the obtained data? Inspired by developments presented by Wagenmakers (Psychonomic Bulletin \& Review, 14, 779\textendash 804, 2007), I provide a tutorial on a Bayesian model selection approach that requires only a simple transformation of sum-of-squares values generated by the standard analysis of variance. This approach generates a graded level of evidence regarding which model (e.g., effect absent [null hypothesis] vs. effect present [alternative hypothesis]) is more strongly supported by the data. This method also obviates admonitions never to speak of accepting the null hypothesis. An Excel worksheet for computing the Bayesian analysis is provided as supplemental material.},
  file = {/Users/Oliver/Zotero/storage/8CQZ4XBU/Masson - 2011 - A tutorial on a practical Bayesian alternative to .pdf;/Users/Oliver/Zotero/storage/J3JC7T5G/10.html},
  journal = {Behavior Research Methods},
  language = {en},
  number = {3}
}

@article{mathur+2016,
  title = {Probing the {{Deep End}} of the {{Milky Way}} with {{Kepler}}: {{Asteroseismic Analysis}} of 854 {{Faint Red Giants Misclassified}} as {{Cool Dwarfs}}},
  shorttitle = {Probing the {{Deep End}} of the {{Milky Way}} with {{Kepler}}},
  author = {Mathur, S. and Garc{\'i}a, R. A. and Huber, D. and Regulo, C. and Stello, D. and Beck, P. G. and Houmani, K. and Salabert, D.},
  year = {2016},
  month = aug,
  volume = {827},
  pages = {50},
  doi = {10.3847/0004-637X/827/1/50},
  abstract = {Asteroseismology has proven to be an excellent tool to determine not only global stellar properties with good precision, but also to infer the stellar structure, dynamics, and evolution for a large sample of Kepler stars. Prior to the launch of the mission, the properties of Kepler targets were inferred from broadband photometry, leading to the Kepler Input Catalog (KIC). The KIC was later revised in the Kepler Star Properties Catalog, based on literature values and an asteroseismic analysis of stars that were unclassified in the KIC. Here, we present an asteroseismic analysis of 45,400 stars that were classified as dwarfs in the Kepler Star Properties Catalog. We found that around 2\% of the sample shows acoustic modes in the typical frequency range that put them in the red-giant category rather than the cool dwarf category. We analyze the asteroseismic properties of these stars, derive their surface gravities, masses, and radii, and present updated effective temperatures and distances. We show that the sample is significantly fainter than the previously known oscillating giants in the Kepler field, with the faintest stars reaching down to a Kepler magnitude of Kp {$\sim$} 16. We demonstrate that 404 stars are at distances beyond 5 kpc and that the stars are significantly less massive than for the original Kepler red-giant sample, consistent with a population of distant halo giants. A comparison with a galactic population model shows that up to 40 stars might be genuine halo giants, which would increase the number of known asteroseismic halo stars by a factor of 4. The detections presented here will provide a valuable sample for galactic archeology studies.},
  file = {/Users/Oliver/Zotero/storage/UMH2V9UP/Mathur et al. - 2016 - Probing the Deep End of the Milky Way with Kepler.pdf;/Users/Oliver/Zotero/storage/PZVUE355/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal},
  language = {en},
  number = {1}
}

@article{mathur+2017,
  title = {Revised {{Stellar Properties}} of {{Kepler Targets}} for the {{Q1}}-17 ({{DR25}}) {{Transit Detection Run}}},
  author = {Mathur, Savita and Huber, Daniel and Batalha, Natalie M. and Ciardi, David R. and Bastien, Fabienne A. and Bieryla, Allyson and Buchhave, Lars A. and Cochran, William D. and Endl, Michael and Esquerdo, Gilbert A. and Furlan, Elise and Howard, Andrew and Howell, Steve B. and Isaacson, Howard and Latham, David W. and MacQueen, Phillip J. and Silva, David R.},
  year = {2017},
  month = apr,
  volume = {229},
  pages = {30},
  doi = {10.3847/1538-4365/229/2/30},
  abstract = {The determination of exoplanet properties and occurrence rates using Kepler data critically depends on our knowledge of the fundamental properties (such as temperature, radius, and mass) of the observed stars. We present revised stellar properties for 197,096 Kepler targets observed between Quarters 1-17 (Q1-17), which were used for the final transiting planet search run by the Kepler Mission (Data Release 25, DR25). Similar to the Q1-16 catalog by Huber et al., the classifications are based on conditioning published atmospheric parameters on a grid of Dartmouth isochrones, with significant improvements in the adopted method and over 29,000 new sources for temperatures, surface gravities, or metallicities. In addition to fundamental stellar properties, the new catalog also includes distances and extinctions, and we provide posterior samples for each stellar parameter of each star. Typical uncertainties are {$\sim$}27\% in radius, {$\sim$}17\% in mass, and {$\sim$}51\% in density, which is somewhat smaller than previous catalogs because of the larger number of improved \{log\}g constraints and the inclusion of isochrone weighting when deriving stellar posterior distributions. On average, the catalog includes a significantly larger number of evolved solar-type stars, with an increase of 43.5\% in the number of subgiants. We discuss the overall changes of radii and masses of Kepler targets as a function of spectral type, with a particular focus on exoplanet host stars.},
  file = {/Users/Oliver/Zotero/storage/VU8UAVH6/Mathur et al. - 2017 - Revised Stellar Properties of Kepler Targets for t.pdf;/Users/Oliver/Zotero/storage/Y4TL6EYY/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal Supplement Series},
  language = {en},
  number = {2}
}

@article{matt+2015,
  title = {The {{Mass}}-Dependence of {{Angular Momentum Evolution}} in {{Sun}}-like {{Stars}}},
  author = {Matt, Sean P. and Brun, A. Sacha and Baraffe, Isabelle and Bouvier, J{\'e}r{\^o}me and Chabrier, Gilles},
  year = {2015},
  month = jan,
  volume = {799},
  pages = {L23},
  doi = {10.1088/2041-8205/799/2/L23},
  abstract = {To better understand the observed distributions of the rotation rate and magnetic activity of Sun-like and low-mass stars, we derive a physically motivated scaling for the dependence of the stellar wind torque on the Rossby number. The torque also contains an empirically derived scaling with stellar mass (and radius), which provides new insight into the mass-dependence of stellar magnetic and wind properties. We demonstrate that this new formulation explains why the lowest mass stars are observed to maintain rapid rotation for much longer than solar-mass stars, and simultaneously why older populations exhibit a sequence of slowly rotating stars, in which the low-mass stars rotate more slowly than solar-mass stars. The model also reproduces some previously unexplained features in the period-mass diagram for the Kepler field, notably: the particular shape of the "upper envelope" of the distribution, suggesting that \textasciitilde 95\% of Kepler field stars with measured rotation periods are younger than \textasciitilde 4 Gyr; and the shape of the "lower envelope," corresponding to the location where stars transition between magnetically saturated and unsaturated regimes.},
  file = {/Users/Oliver/Zotero/storage/W9T6KKRK/Matt et al. - 2015 - The Mass-dependence of Angular Momentum Evolution .pdf;/Users/Oliver/Zotero/storage/MQVW48R8/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal},
  keywords = {Core Gyrochronology},
  language = {en},
  number = {2}
}

@article{maxted+2015,
  title = {Comparison of Gyrochronological and Isochronal Age Estimates for Transiting Exoplanet Host Stars},
  author = {Maxted, P. F. L. and Serenelli, A. M. and Southworth, J.},
  year = {2015},
  month = may,
  volume = {577},
  pages = {A90},
  issn = {0004-6361},
  doi = {10.1051/0004-6361/201525774},
  abstract = {Context. Tidal interactions between planets and their host stars are not
well understood, but may be an important factor in their formation,
structure, and evolution. Previous studies suggest that these tidal
interactions may be responsible for discrepancies between the ages of
exoplanet host stars estimated using stellar models (isochronal age
estimates) and age estimates based on the stars' rotation periods
(gyrochronological age estimates). Recent improvements in our
understanding of the rotational evolution of single stars and a
substantial increase in the number of exoplanet host stars with accurate
rotation period measurements make it worthwhile to revisit this
question. Aims: Our aim is to determine whether the
gyrochronological age estimates for transiting exoplanet host stars with
accurate rotation period measurements are consistent with their
isochronal age estimates, and whether this is indicative of tidal
interaction between the planets and their host stars. Methods: We
have compiled a sample of 28 transiting exoplanet host stars with
measured rotation periods, including two stars (HAT-P-21 and WASP-5) for
which the rotation period based on the light curve modulation is
reported here for the first time. We use our recently developed Bayesian
Markov chain Monte Carlo method to determine the joint posterior
distribution for the mass and age of each star in the sample. We extend
our Bayesian method to include a calculation of the posterior
distribution of the gyrochronological age estimate that accounts for the
uncertainties in the mass and age, the strong correlation between these
values, and the uncertainties in the mass-rotation-age calibration. Results: The gyrochronological age estimate ({$\tau$}gyro) is
significantly lower than the isochronal age estimate for about half of
the stars in our sample. Tidal interactions between the star and planet
are a reasonable explanation for this discrepancy in some cases, but not
all. The distribution of {$\tau$}gyro values is evenly spread
from very young ages up to a maximum value of a few Gyr, i.e. there is
no obvious pile-up of stars at very low or very high values of
{$\tau$}gyro as might be expected if some evolutionary or
selection effect were biasing the age distribution of the stars in this
sample. There is no clear correlation between {$\tau$}gyro and
the strength of the tidal force on the star due to the innermost planet.
There is clear evidence that the isochronal age estimates for some
K-type stars are too high, and this may also be the case for some G-type
stars. This may be the result of magnetic inhibition of convection. The
densities of HAT-P-11 and WASP-84 are too high to be reproduced by any
stellar models within the observed constraints on effective temperature
and metallicity. These stars may have strongly enhanced helium
abundances. There is currently no satisfactory explanation for the
discrepancy between the young age for CoRoT-2 estimated from either
gyrochronology or its high lithium abundance, and the extremely old age
for its K-type stellar companion inferred from its very low X-ray flux.
 Conclusions: There is now strong evidence that the
gyrochronological age estimates for some transiting exoplanet host stars
are significantly lower than the isochronal age estimates, but it is not
always clear that this is good evidence for tidal interactions between
the star and the planet.},
  file = {/Users/Oliver/Zotero/storage/S4BKR56L/Maxted et al. - 2015 - Comparison of gyrochronological and isochronal age.pdf},
  journal = {Astronomy and Astrophysics},
  keywords = {planet-star interactions,stars: solar-type}
}

@article{mazumdar+2014,
  title = {Measurement of Acoustic Glitches in Solar-Type Stars from Oscillation Frequencies Observed by {{Kepler}}},
  author = {Mazumdar, A. and Monteiro, M. J. P. F. G. and Ballot, J. and Antia, H. M. and Basu, S. and Houdek, G. and Mathur, S. and Cunha, M. S. and Aguirre, V. Silva and Garcia, R. A. and Salabert, D. and Verner, G. A. and {Christensen-Dalsgaard}, J. and Metcalfe, T. S. and Sanderfer, D. T. and Seader, S. E. and Smith, J. C. and Chaplin, W. J.},
  year = {2014},
  month = jan,
  volume = {782},
  pages = {18},
  issn = {0004-637X, 1538-4357},
  doi = {10.1088/0004-637X/782/1/18},
  abstract = {For the very best and brightest asteroseismic solar-type targets observed by Kepler, the frequency precision is sufficient to determine the acoustic depths of the surface convective layer and the helium ionization zone. Such sharp features inside the acoustic cavity of the star, which we call acoustic glitches, create small oscillatory deviations from the uniform spacing of frequencies in a sequence of oscillation modes with the same spherical harmonic degree. We use these oscillatory signals to determine the acoustic locations of such features in 19 solar-type stars observed by the Kepler mission. Four independent groups of researchers utilized the oscillation frequencies themselves, the second differences of the frequencies and the ratio of the small and large separation to locate the base of the convection zone and the second helium ionization zone. Despite the significantly different methods of analysis, good agreement was found between the results of these four groups, barring a few cases. These results also agree reasonably well with the locations of these layers in representative models of the stars. These results firmly establish the presence of the oscillatory signals in the asteroseismic data and the viability of several techniques to determine the location of acoustic glitches inside stars.},
  archivePrefix = {arXiv},
  eprint = {1312.4907},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/PMYUKBZZ/Mazumdar et al. - 2014 - Measurement of acoustic glitches in solar-type sta.pdf;/Users/Oliver/Zotero/storage/NLMSZS72/1312.html},
  journal = {The Astrophysical Journal},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  number = {1}
}

@inproceedings{mckinney2010,
  title = {Data {{Structures}} for {{Statistical Computing}} in {{Python}}},
  booktitle = {Proceedings of the 9th {{Python}} in {{Science Conference}}},
  author = {McKinney, Wes},
  year = {2010},
  pages = {51--56},
  file = {/Users/Oliver/Zotero/storage/7D4EYGGN/McKinney - 2010 - Data Structures for Statistical Computing in Pytho.pdf;/Users/Oliver/Zotero/storage/PLDAT3I8/mckinney.html}
}

@article{mcquillan+2014,
  title = {Rotation {{Periods}} of 34,030 {{Kepler Main}}-{{Sequence Stars}}: {{The Full Autocorrelation Sample}}},
  shorttitle = {Rotation {{Periods}} of 34,030 {{Kepler Main}}-{{Sequence Stars}}},
  author = {McQuillan, Amy and Mazeh, Tsevi and Aigrain, Suzanne},
  year = {2014},
  month = mar,
  volume = {211},
  pages = {24},
  issn = {0067-0049, 1538-4365},
  doi = {10.1088/0067-0049/211/2/24},
  abstract = {We analyzed 3 years of data from the Kepler space mission to derive rotation periods of main-sequence stars below 6500 K. Our automated autocorrelation-based method detected rotation periods between 0.2 and 70 days for 34,030 (25.6\%) of the 133,030 main-sequence Kepler targets (excluding known eclipsing binaries and Kepler Objects of Interest), making this the largest sample of stellar rotation periods to date. In this paper we consider the detailed features of the now well-populated period-temperature distribution and demonstrate that the period bimodality, first seen by McQuillan, Aigrain \& Mazeh (2013) in the M-dwarf sample, persists to higher masses, becoming less visible above 0.6 M\_sun. We show that these results are globally consistent with the existing ground-based rotation-period data and find that the upper envelope of the period distribution is broadly consistent with a gyrochronological age of 4.5 Gyrs, based on the isochrones of Barnes (2007), Mamajek \& Hillenbrand (2008) and Meibom et al. (2009). We also performed a detailed comparison of our results to those of Reinhold et al. (2013) and Nielsen et al. (2013), who have measured rotation periods of field stars observed by Kepler. We examined the amplitude of periodic variability for the stars with detected rotation periods, and found a typical range between \textasciitilde 950 ppm (5th percentile) and \textasciitilde 22,700 ppm (95th percentile), with a median of \textasciitilde 5,600 ppm. We found typically higher amplitudes for shorter periods and lower effective temperatures, with an excess of low-amplitude stars above \textasciitilde 5400 K.},
  archivePrefix = {arXiv},
  eprint = {1402.5694},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/QLLKPTIU/McQuillan et al. - 2014 - Rotation Periods of 34,030 Kepler Main-Sequence St.pdf;/Users/Oliver/Zotero/storage/RBYCCM8K/1402.html},
  journal = {The Astrophysical Journal Supplement Series},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  number = {2}
}

@article{mehrabi+2016,
  title = {Magnetic Activity Analysis for a Sample of {{G}}-Type Main Sequence \textbackslash emph\{\vphantom\}{{Kepler}}\vphantom\{\} Targets},
  author = {Mehrabi, A. and He, H. and Khosroshahi, H.},
  year = {2016},
  month = nov,
  abstract = {The variation of a stellar light curve owing to the rotational modulation by the magnetic features (starspots and faculae) on the star's surface can be used to investigate the magnetic properties of the host star. In this paper, we use the periodicity and magnitude of the light-curve variation, as two proxies, suggested by (He et al. 2015), to study the stellar magnetic properties for a large sample of G-type main sequence \textbackslash emph\{Kepler\} targets, for which the rotation periods recently determined by (McQuillan et al. 2014). By analyzing the correlation between the two magnetic proxies, it is found that: (1) The two proxies are positively correlated for most of the stars in our sample, and the percentages of negative, zero, and positive correlation are \$4.27\textbackslash\%\$, \$6.81\textbackslash\%\$, and \$88.91\textbackslash\%\$, respectively; (2) Negative correlation stars cannot have large magnitude of light-curve variation; (3) with the increase of rotation period, the relative number of positive correlation stars decreases and the negative correlation one increases. These results indicate that the stars with shorter rotation period tend to have positive correlation between the two proxies, and a good portion of the positive correlation stars have larger magnitude of light-curve variation (and hence more intense magnetic activities) than the negative correlation stars.},
  archivePrefix = {arXiv},
  eprint = {1611.07262},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/SA232Z3W/Mehrabi et al. - 2016 - Magnetic activity analysis for a sample of G-type .pdf;/Users/Oliver/Zotero/storage/QF8DCQAV/1611.html},
  journal = {arXiv:1611.07262 [astro-ph]},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{meibom+2009,
  title = {Stellar {{Rotation}} in {{M35}}: {{Mass}}-{{Period Relations}}, {{Spin}}-{{Down Rates}}, and {{Gyrochronology}}},
  shorttitle = {Stellar {{Rotation}} in {{M35}}},
  author = {Meibom, S{\o}ren and Mathieu, Robert D. and Stassun, Keivan G.},
  year = {2009},
  month = apr,
  volume = {695},
  pages = {679},
  doi = {10.1088/0004-637X/695/1/679},
  abstract = {We present the results of a five month photometric time-series survey for stellar rotation over a 40' \texttimes{} 40' field centered on the 150 Myr open cluster M35. We report rotation periods for 441 stars within this field and determine their cluster membership and binarity based on a decade-long radial velocity survey, proper-motion measurements, and multiband photometric observations. We find that 310 of the stars with measured rotation periods are late-type members of M35. The distribution of rotation periods for cluster members span more than 2 orders of magnitude from \textasciitilde 0.1 to 15 days, not constrained by the sampling frequency and the timespan of the survey. With an age between the zero-age main sequence and the Hyades, and with \textasciitilde 6 times more rotation periods than measured in the Pleiades, M35 permit detailed studies of early rotational evolution of late-type stars. Nearly 80\% of the 310 rotators lie on two distinct sequences in the color-period plane, and define clear relations between stellar rotation period and color (mass). The M35 color-period diagram enables us to determine timescales for the transition between the two rotational states, of \textasciitilde 60 Myr and \textasciitilde 140 Myr for G and K dwarfs, respectively. These timescales are inversely related to the mass of the convective envelope, and offer constraints on the rates of internal and external angular momentum transport and of the evolution of stellar dynamos. A comparison to the Hyades, confirm the Skumanich spin-down dependence for G dwarfs on one rotational state, but suggest that K dwarfs spin down more slowly. The locations of the rotational sequences in the M35 color-period diagram support the use of rotational isochrones to determine ages for coeval stellar populations. We use such gyrochronology to determine "gyro-ages" for M35 from 134 Myr to 161 Myr. We use the M35 data to evaluate new color dependences for the rotational isochrones. WIYN Open Cluster Study. XXXV.},
  file = {/Users/Oliver/Zotero/storage/9RUQV2KB/Meibom et al. - 2009 - Stellar Rotation in M35 Mass-Period Relations, Sp.pdf;/Users/Oliver/Zotero/storage/7GX8LPJW/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal},
  keywords = {Core Gyrochronology},
  language = {en},
  number = {1}
}

@article{meibom+2015,
  title = {A Spin-down Clock for Cool Stars from Observations of a 2.5-Billion-Year-Old Cluster},
  author = {Meibom, S{\o}ren and Barnes, Sydney A. and Platais, Imants and Gilliland, Ronald L. and Latham, David W. and Mathieu, Robert D.},
  year = {2015},
  month = jan,
  volume = {517},
  pages = {589},
  doi = {10.1038/nature14118},
  abstract = {The ages of the most common stars--low-mass (cool) stars like the Sun, and smaller--are difficult to derive because traditional dating methods use stellar properties that either change little as the stars age or are hard to measure. The rotation rates of all cool stars decrease substantially with time as the stars steadily lose their angular momenta. If properly calibrated, rotation therefore can act as a reliable determinant of their ages based on the method of gyrochronology. To calibrate gyrochronology, the relationship between rotation period and age must be determined for cool stars of different masses, which is best accomplished with rotation period measurements for stars in clusters with well-known ages. Hitherto, such measurements have been possible only in clusters with ages of less than about one billion years, and gyrochronology ages for older stars have been inferred from model predictions. Here we report rotation period measurements for 30 cool stars in the 2.5-billion-year-old cluster NGC 6819. The periods reveal a well-defined relationship between rotation period and stellar mass at the cluster age, suggesting that ages with a precision of order 10 per cent can be derived for large numbers of cool Galactic field stars.},
  file = {/Users/Oliver/Zotero/storage/26ZVXWDH/Meibom et al. - 2015 - A spin-down clock for cool stars from observations.pdf;/Users/Oliver/Zotero/storage/6SKQANVI/ui.adsabs.harvard.edu.html},
  journal = {Nature},
  keywords = {Core Gyrochronology},
  language = {en},
  number = {7536}
}

@article{messina+2017,
  title = {Impact of Photometric Variability on Age and Mass Determination of {{Young Stellar Objects}}: {{A}} Case Study on {{Orion Nebula Cluster}}},
  shorttitle = {Impact of Photometric Variability on Age and Mass Determination of {{Young Stellar Objects}}},
  author = {Messina, Sergio and Parihar, Padmakar S. and Distefano, Elisa},
  year = {2017},
  month = feb,
  abstract = {In case of pre-main sequence objects, the only way to determine age and mass is by fitting theoretical isochrones on color-magnitude (alternatively luminosity-temperature) diagrams. Since young stellar objects exhibit photometric variability over wide range in magnitude and colors, the age and mass determined by fitting isochrones is expected to be inaccurate, if not erroneous. These in turn will badly affect any study carried out on age spread and process of star formation. Since we have carried out very extensive photometric observations of the Orion Nebula Cluster (ONC), we decided to use our multi-band data to explore the influence of variability in determining mass and age of cluster members. In this study, we get the amplitudes of the photometric variability in V, R, and I optical bands of a sample of 346 ONC members and use it to investigate how the variability affects the inferred masses and ages and if it alone can take account for the age spread among the ONC members reported by earlier studies. We find that members that show periodic and smooth photometric rotational modulation have their masses and ages unaffected by variability. On other hand, we found that members with periodic but very scattered photometric rotational modulation and members with irregular variability have their masses and ages significantly affected. Moreover, using Hertzsprung-Russell (HR) diagrams we find that the observed I band photometric variability can take account of only a fraction (about 50\%) of the inferred age spread, whereas the V band photometric variability is large enough to mask any age spread.},
  archivePrefix = {arXiv},
  eprint = {1702.01592},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/W8ENDT8H/Messina et al. - 2017 - Impact of photometric variability on age and mass .pdf;/Users/Oliver/Zotero/storage/6BPPN3DH/1702.html},
  journal = {arXiv:1702.01592 [astro-ph]},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{metcalfe+2012,
  title = {First {{Results}} from the {{Asteroseismic Modeling Portal}}},
  author = {Metcalfe, T. S. and Mathur, S. and Do{\u g}an, G. and Woitaszek, M.},
  year = {2012},
  month = sep,
  volume = {462},
  pages = {213},
  abstract = {Asteroseismology will soon place our understanding of the Sun into a broader context by providing structural information for hundreds of solar-type stars. In the past, ground-based data on solar-like oscillations have emerged slowly enough that we could try to model one star at a time. NASA's Kepler mission is now producing asteroseismic data for hundreds of stars every few months, so a hands-on approach is a luxury we can no longer afford. We have developed a stellar model-fitting pipeline, which employs a parallel genetic algorithm to match observations from the Kepler mission. We have validated the method using Sun-as-a-star observations as well as data from a wide variety of solar-type stars. The pipeline is now available through the Asteroseismic Modeling Portal (AMP), a Science Gateway website tied to supercomputing resources on the TeraGrid. In this talk, I provided an overview of AMP and presented some of the first results from its automated analysis of both ground-based and space-based asteroseismic data sets.},
  file = {/Users/Oliver/Zotero/storage/R8RHQPA7/Metcalfe et al. - 2012 - First Results from the Asteroseismic Modeling Port.pdf;/Users/Oliver/Zotero/storage/8P8QHR8E/ui.adsabs.harvard.edu.html},
  journal = {Progress in Solar/Stellar Physics with Helio- and Asteroseismology},
  language = {en}
}

@article{metcalfe+2012a,
  title = {Asteroseismology of the {{Solar Analogs}} 16 {{Cyg A}} and {{B}} from {{Kepler Observations}}},
  author = {Metcalfe, T. S. and Chaplin, W. J. and Appourchaux, T. and Garc{\'i}a, R. A. and Basu, S. and Brand{\~a}o, I. and Creevey, O. L. and Deheuvels, S. and Do{\v g}an, G. and Eggenberger, P. and Karoff, C. and Miglio, A. and Stello, D. and Y{\i}ld{\i}z, M. and {\c C}elik, Z. and Antia, H. M. and Benomar, O. and Howe, R. and R{\'e}gulo, C. and Salabert, D. and Stahn, T. and Bedding, T. R. and Davies, G. R. and Elsworth, Y. and Gizon, L. and Hekker, S. and Mathur, S. and Mosser, B. and Bryson, S. T. and Still, M. D. and {Christensen-Dalsgaard}, J. and Gilliland, R. L. and Kawaler, S. D. and Kjeldsen, H. and Ibrahim, K. A. and Klaus, T. C. and Li, J.},
  year = {2012},
  month = mar,
  volume = {748},
  pages = {L10},
  issn = {0004-637X},
  doi = {10.1088/2041-8205/748/1/L10},
  abstract = {The evolved solar-type stars 16 Cyg A and B have long been studied as solar analogs, yielding a glimpse into the future of our own Sun. The orbital period of the binary system is too long to provide meaningful dynamical constraints on the stellar properties, but asteroseismology can help because the stars are among the brightest in the Kepler field. We present an analysis of three months of nearly uninterrupted
photometry of 16 Cyg A and B from the Kepler space telescope. We extract a total of 46 and 41 oscillation frequencies for the two components, respectively, including a clear detection of octupole (l = 3) modes in both stars. We derive the properties of each star independently using the Asteroseismic Modeling Portal, fitting the individual oscillation frequencies and other observational constraints simultaneously. We evaluate the systematic uncertainties from an ensemble of results generated by a variety of stellar evolution codes and fitting methods. The optimal models derived by fitting each component individually yield a common age (t = 6.8 {$\pm$} 0.4 Gyr) and initial composition (Z
i = 0.024 {$\pm$} 0.002, Y i = 0.25 {$\pm$}
0.01) within the uncertainties, as expected for the components of a binary system, bolstering our confidence in the reliability of
asteroseismic techniques. The longer data sets that will ultimately become available will allow future studies of differential rotation, convection zone depths, and long-term changes due to stellar activity cycles.},
  file = {/Users/Oliver/Zotero/storage/6HR8ZFNW/Metcalfe et al. - 2012 - Asteroseismology of the Solar Analogs 16 Cyg A and.pdf},
  journal = {The Astrophysical Journal Letters},
  keywords = {stars: fundamental parameters,stars: individual: HD 186408 HD 186427,stars: interiors,stars: oscillations,stars: solar-type}
}

@article{metcalfe+2014,
  title = {Properties of 42 {{Solar}}-Type {{Kepler Targets}} from the {{Asteroseismic Modeling Portal}}},
  author = {Metcalfe, T. S. and Creevey, O. L. and Do{\u g}an, G. and Mathur, S. and Xu, H. and Bedding, T. R. and Chaplin, W. J. and {Christensen-Dalsgaard}, J. and Karoff, C. and Trampedach, R. and Benomar, O. and Brown, B. P. and Buzasi, D. L. and Campante, T. L. and {\c C}elik, Z. and Cunha, M. S. and Davies, G. R. and Deheuvels, S. and Derekas, A. and Mauro, Di and P, M. and Garc{\'i}a, R. A. and Guzik, J. A. and Howe, R. and MacGregor, K. B. and Mazumdar, A. and Montalb{\'a}n, J. and Monteiro, M. J. P. F. G. and Salabert, D. and Serenelli, A. and Stello, D. and Ste\&șacute and Licki, M. and Suran, M. D. and Y{\i}ld{\i}z, M. and Aksoy, C. and Elsworth, Y. and Gruberbauer, M. and Guenther, D. B. and Lebreton, Y. and Molaverdikhani, K. and Pricopi, D. and Simoniello, R. and White, T. R.},
  year = {2014},
  month = oct,
  volume = {214},
  pages = {27},
  doi = {10.1088/0067-0049/214/2/27},
  abstract = {Recently the number of main-sequence and subgiant stars exhibiting solar-like oscillations that are resolved into individual mode frequencies has increased dramatically. While only a few such data sets were available for detailed modeling just a decade ago, the Kepler mission has produced suitable observations for hundreds of new targets. This rapid expansion in observational capacity has been accompanied by a shift in analysis and modeling strategies to yield uniform sets of derived stellar properties more quickly and easily. We use previously published asteroseismic and spectroscopic data sets to provide a uniform analysis of 42 solar-type Kepler targets from the Asteroseismic Modeling Portal. We find that fitting the individual frequencies typically doubles the precision of the asteroseismic radius, mass, and age compared to grid-based modeling of the global oscillation properties, and improves the precision of the radius and mass by about a factor of three over empirical scaling relations. We demonstrate the utility of the derived properties with several applications.},
  file = {/Users/Oliver/Zotero/storage/334RPZSQ/Metcalfe et al. - 2014 - Properties of 42 Solar-type Kepler Targets from th.pdf;/Users/Oliver/Zotero/storage/TI8BKYRL/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal Supplement Series},
  language = {en},
  number = {2}
}

@article{metcalfe+2016,
  title = {Stellar {{Evidence That}} the {{Solar Dynamo May Be}} in {{Transition}}},
  author = {Metcalfe, Travis S. and Egeland, Ricky and {van Saders}, Jennifer},
  year = {2016},
  month = jul,
  volume = {826},
  pages = {L2},
  issn = {0004-637X},
  doi = {10.3847/2041-8205/826/1/L2},
  abstract = {Precise photometry from the Kepler space telescope allows not only the measurement of rotation in solar-type field stars, but also the
determination of reliable masses and ages from asteroseismology. These critical data have recently provided the first opportunity to calibrate rotation-age relations for stars older than the Sun. The
evolutionary picture that emerges is surprising: beyond middle-age the efficiency of magnetic braking is dramatically reduced, implying a fundamental change in angular momentum loss beyond a critical Rossby number (Ro \texttildelow{} 2). We compile published chromospheric activity
measurements for the sample of Kepler asteroseismic targets that were used to establish the new rotation-age relations. We use these
data along with a sample of well-characterized solar analogs from the Mount Wilson HK survey to develop a qualitative scenario connecting the evolution of chromospheric activity to a fundamental shift in the character of differential rotation. We conclude that the Sun may be in a transitional evolutionary phase, and that its magnetic cycle might represent a special case of stellar dynamo theory.},
  journal = {The Astrophysical Journal Letters},
  keywords = {stars: activity,stars: evolution,stars: magnetic field,stars: rotation,stars: solar-type}
}

@article{metcalfe+2017,
  title = {The {{Impact}} of {{Gaia DR1}} on {{Asteroseismic Inferences}} from {{Kepler}}},
  author = {Metcalfe, Travis and Creevey, Orlagh and {van Saders}, Jennifer},
  year = {2017},
  month = jan,
  abstract = {The Kepler mission has been fantastic for asteroseismology of solar-type stars, but the targets are typically quite distant. As a consequence, the reliability of asteroseismic modeling has been limited by the precision of additional constraints from high-resolution spectroscopy and parallax measurements. A precise luminosity is particularly useful to minimize potential biases due to the intrinsic correlation between stellar mass and initial helium abundance. We have applied the latest version of the Asteroseismic Modeling Portal (AMP) to the complete Kepler data sets for 30 stars with known rotation rates and chromospheric activity levels. We compare the stellar properties derived with and without the measured parallaxes from the first data release of Gaia. We find that in most cases the masses and ages inferred from asteroseismology shift within their uncertainties. For a few targets that show larger shifts, the updated stellar properties only strengthen previous conclusions about anomalous rotation in middle-aged stars.},
  archivePrefix = {arXiv},
  eprint = {1701.08746},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/U96H4GTF/Metcalfe et al. - 2017 - The Impact of Gaia DR1 on Asteroseismic Inferences.pdf;/Users/Oliver/Zotero/storage/DFSDPHAD/1701.html},
  journal = {arXiv:1701.08746 [astro-ph]},
  keywords = {Astrophysics - Earth and Planetary Astrophysics,Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{metcalfe+2019,
  title = {{{LBT}}/{{PEPSI Spectropolarimetry}} of a {{Magnetic Morphology Shift}} in {{Old Solar}}-Type {{Stars}}},
  author = {Metcalfe, Travis S. and Kochukhov, Oleg and Ilyin, Ilya V. and Strassmeier, Klaus G. and {Godoy-Rivera}, Diego and Pinsonneault, Marc H.},
  year = {2019},
  month = dec,
  abstract = {Solar-type stars are born with relatively rapid rotation and strong magnetic fields. Through a process known as magnetic braking, the rotation slows over time as stellar winds gradually remove angular momentum from the system. The rate of angular momentum loss depends sensitively on the magnetic morphology, with the dipole field exerting the largest torque on the star. Recent observations suggest that the efficiency of magnetic braking may decrease dramatically in stars near the middle of their main-sequence lifetimes. One hypothesis to explain this reduction in efficiency is a shift in magnetic morphology from predominantly larger to smaller spatial scales. We aim to test this hypothesis with spectropolarimetric measurements of two stars that sample chromospheric activity levels on opposite sides of the proposed magnetic transition. As predicted, the more active star (HD 100180) exhibits a significant circular polarization signature due to a non-axisymmetric large-scale magnetic field, while the less active star (HD 143761) shows no significant signal. We identify analogs of the two stars among a sample of well-characterized Kepler targets, and we predict that the asteroseismic age of HD 143761 from future TESS observations will substantially exceed the age expected from gyrochronology. We conclude that a shift in magnetic morphology likely contributes to the loss of magnetic braking in middle-aged stars, which appears to coincide with the shutdown of their global dynamos.},
  archivePrefix = {arXiv},
  eprint = {1912.01186},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/5YU9VX9W/Metcalfe et al. - 2019 - LBTPEPSI Spectropolarimetry of a Magnetic Morphol.pdf;/Users/Oliver/Zotero/storage/XGJNYAH4/1912.html},
  journal = {arXiv:1912.01186 [astro-ph]},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{metcalfe+2019a,
  title = {{{LBT}}/{{PEPSI Spectropolarimetry}} of a {{Magnetic Morphology Shift}} in {{Old Solar}}-Type {{Stars}}},
  author = {Metcalfe, T. S. and Kochukhov, O. and Ilyin, I. V. and Strassmeier, K. G. and {Godoy-Rivera}, D. and Pinsonneault, M. H.},
  year = {2019},
  month = dec,
  volume = {887},
  pages = {L38},
  issn = {0004-637X},
  doi = {10.3847/2041-8213/ab5e48},
  abstract = {Solar-type stars are born with relatively rapid rotation and strong
magnetic fields. Through a process known as magnetic braking, the
rotation slows over time as stellar winds gradually remove angular
momentum from the system. The rate of angular momentum loss depends
sensitively on the magnetic morphology, with the dipole field exerting
the largest torque on the star. Recent observations suggest that the
efficiency of magnetic braking may decrease dramatically in stars near
the middle of their main-sequence lifetimes. One hypothesis to explain
this reduction in efficiency is a shift in magnetic morphology from
predominantly larger to smaller spatial scales. We aim to test this
hypothesis with spectropolarimetric measurements of two stars that
sample chromospheric activity levels on opposite sides of the proposed
magnetic transition. As predicted, the more active star (HD 100180)
exhibits a significant circular polarization signature due to a
nonaxisymmetric large-scale magnetic field, while the less active star
(HD 143761) shows no significant signal. We identify analogs of the two
stars among a sample of well-characterized Kepler targets, and we
predict that the asteroseismic age of HD 143761 from future Transiting
Exoplanet Survey Satellite observations will substantially exceed the
age expected from gyrochronology. We conclude that a shift in magnetic
morphology likely contributes to the loss of magnetic braking in
middle-aged stars, which appears to coincide with the shutdown of their
global dynamos.

The LBT is an international collaboration among institutions in the
United States, Italy and Germany. LBT Corporation partners are: The
University of Arizona on behalf of the Arizona Board of Regents;
Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft,
Germany, representing the Max-Planck Society, The Leibniz Institute for
Astrophysics Potsdam, and Heidelberg University; The Ohio State
University, and The Research Corporation, on behalf of The University of
Notre Dame, University of Minnesota and University of Virginia.},
  file = {/Users/Oliver/Zotero/storage/JKHP2V7R/Metcalfe et al. - 2019 - LBTPEPSI Spectropolarimetry of a Magnetic Morphol.pdf},
  journal = {The Astrophysical Journal Letters},
  keywords = {Solar analogs,Spectropolarimetry,Stellar evolution,Stellar magnetic fields}
}

@article{metcalfe+egeland2019,
  title = {Understanding the {{Limitations}} of {{Gyrochronology}} for {{Old Field Stars}}},
  author = {Metcalfe, Travis S. and Egeland, Ricky},
  year = {2019},
  month = jan,
  volume = {871},
  pages = {39},
  issn = {1538-4357},
  doi = {10.3847/1538-4357/aaf575},
  abstract = {Nearly half a century has passed since the initial indications that stellar rotation slows while chromospheric activity weakens with a power-law dependence on age, the so-called Skumanich relations. Subsequent characterization of the mass-dependence of this behavior up to the age of the Sun led to the advent of gyrochronology, which uses the rotation rate of a star to infer its age from an empirical calibration. The efficacy of the method relies on predictable angular momentum loss from a stellar wind entrained in the large-scale magnetic field produced by global dynamo action. Recent observational evidence suggests that the global dynamo begins to shut down near the middle of a star's main-sequence lifetime, leading to a disruption in the production of large-scale magnetic field, a dramatic reduction in angular momentum loss, and a breakdown of gyrochronology relations. For solar-type stars this transition appears to occur near the age of the Sun, when rotation becomes too slow to imprint Coriolis forces on the global convective patterns, reducing the shear induced by differential rotation, and disrupting the large-scale dynamo. We use data from Barnes (2007) to reveal the signature of this transition in the observations that were originally used to validate gyrochronology. We propose that chromospheric activity may ultimately provide a more reliable age indicator for older stars, and we suggest that asteroseismology can be used to help calibrate activity-age relations for field stars beyond the middle of their main-sequence lifetimes.},
  archivePrefix = {arXiv},
  eprint = {1811.11905},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/4IX7UMB9/Metcalfe and Egeland - 2019 - Understanding the Limitations of Gyrochronology fo.pdf},
  journal = {The Astrophysical Journal},
  keywords = {Astrophysics - Earth and Planetary Astrophysics,Astrophysics - Solar and Stellar Astrophysics},
  number = {1}
}

@article{metcalfe+vansaders2017,
  title = {Magnetic {{Evolution}} and the {{Disappearance}} of {{Sun}}-like {{Activity Cycles}}},
  author = {Metcalfe, Travis S. and {van Saders}, Jennifer},
  year = {2017},
  month = sep,
  volume = {292},
  pages = {126},
  issn = {0038-0938, 1573-093X},
  doi = {10.1007/s11207-017-1157-5},
  abstract = {After decades of effort, the solar activity cycle is exceptionally well characterized but it remains poorly understood. Pioneering work at the Mount Wilson Observatory demonstrated that other sun-like stars also show regular activity cycles, and suggested two possible relationships between the rotation rate and the length of the cycle. Neither of these relationships correctly describe the properties of the Sun, a peculiarity that demands explanation. Recent discoveries have started to shed light on this issue, suggesting that the Sun's rotation rate and magnetic field are currently in a transitional phase that occurs in all middle-aged stars. Motivated by these developments, we identify the manifestation of this magnetic transition in the best available data on stellar cycles. We propose a reinterpretation of previously published observations to suggest that the solar cycle may be growing longer on stellar evolutionary timescales, and that the cycle might disappear sometime in the next 0.8-2.4 Gyr. Future tests of this hypothesis will come from ground-based activity monitoring of Kepler targets that span the magnetic transition, and from asteroseismology with the TESS mission to determine precise masses and ages for bright stars with known cycles.},
  archivePrefix = {arXiv},
  eprint = {1705.09668},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/K4C38QIP/Metcalfe and van Saders - 2017 - Magnetic Evolution and the Disappearance of Sun-li.pdf;/Users/Oliver/Zotero/storage/MCTMKHQC/1705.html},
  journal = {Solar Physics},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  number = {9}
}

@article{michalik+2015,
  title = {Gaia Astrometry for Stars with Too Few Observations. {{A Bayesian}} Approach},
  author = {Michalik, Daniel and Lindegren, Lennart and Hobbs, David and Butkevich, Alexey G.},
  year = {2015},
  month = nov,
  volume = {583},
  pages = {A68},
  issn = {0004-6361},
  doi = {10.1051/0004-6361/201526936},
  abstract = {Context. The astrometric solution for Gaia aims to determine at least five parameters for each star, representing its position, parallax, and proper motion, together with appropriate estimates of their
uncertainties and correlations. This requires at least five distinct observations per star. In the early data reductions the number of observations may be insufficient for a five-parameter solution, and even after the full mission many stars will remain under-observed, including faint stars at the detection limit and transient objects. In such cases it is reasonable to determine only the two position parameters. The formal uncertainties of such a two-parameter solution would however grossly underestimate the actual errors in position, due to the
neglected parallax and proper motion. Aims: We aim to develop a recipe to calculate sensible formal uncertainties that can be used in all cases of under-observed stars. Methods: Prior information about the typical ranges of stellar parallaxes and proper motions is incorporated in the astrometric solution by means of Bayes' rule. Numerical simulations based on the Gaia Universe Model Snapshot (GUMS) are used to investigate how the prior influences the actual errors and formal uncertainties when different amounts of Gaia observations are available. We develop a criterion for the optimum choice of priors, apply it to a wide range of cases, and derive a global approximation of the optimum prior as a function of magnitude and galactic coordinates. Results: The feasibility of the Bayesian approach is demonstrated through global astrometric solutions of simulated Gaia observations. With an appropriate prior it is possible to derive sensible positions with realistic error estimates for any number of available observations. Even though this recipe works also for well-observed stars it should not be used where a good five-parameter astrometric solution can be obtained without a prior. Parallaxes and proper motions from a solution using priors are always biased and should not be used.},
  file = {/Users/Oliver/Zotero/storage/35H6GPDF/Michalik et al. - 2015 - Gaia astrometry for stars with too few observation.pdf},
  journal = {Astronomy and Astrophysics},
  keywords = {astrometry,methods: data analysis,methods: numerical,parallaxes,proper motions,space vehicles: instruments}
}

@article{miglio+2009,
  title = {Probing Populations of Red Giants in the Galactic Disk with {{CoRoT}}},
  author = {Miglio, A. and Montalb{\'a}n, J. and Baudin, F. and Eggenberger, P. and Noels, A. and Hekker, S. and De Ridder, J. and Weiss, W. and Baglin, A.},
  year = {2009},
  month = sep,
  volume = {503},
  pages = {L21},
  doi = {10.1051/0004-6361/200912822},
  abstract = {Context: The detection with CoRoT of solar-like oscillations in nearly 800 red giants in the first 150-days long observational run paves the way for detailed studies of populations of galactic-disk red giants. \\
Aims: We investigate which information on the observed population can be recovered by the distribution of the observed seismic constraints: the frequency of maximum oscillation power ({$\nu\_$}max) and the large frequency separation ({$\increment\nu$}). \\
Methods: We propose to use the observed distribution of {$\nu\_$}max and of {$\increment\nu$} as a tool for investigating the properties of galactic red-giant stars through comparison with simulated distributions based on synthetic stellar populations. \\
Results: We can clearly identify the bulk of the red giants observed by CoRoT as red-clump stars, i.e. post-flash core-He-burning stars. The distribution of {$\nu\_$}max and of {$\increment\nu$} gives us access to the distribution of the stellar radius and mass, and thus represent a most promising probe of the age and star formation rate of the disk, and of the mass-loss rate during the red-giant branch. \\
Conclusions: CoRoT observations are supplying seismic constraints for the most populated class of He-burning stars in the galactic disk. This opens a new access gate to probing the properties of red-giant stars that, coupled with classical observations, promises to extend our knowledge of these advanced phases of stellar evolution and to add relevant constraints to models of composite stellar populations in the Galaxy. The CoRoT space mission was developed and is operated by the French space agency CNES, with the participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain.},
  file = {/Users/Oliver/Zotero/storage/HZ2SFIHQ/Miglio et al. - 2009 - Probing populations of red giants in the galactic .pdf;/Users/Oliver/Zotero/storage/NRSRB99L/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en},
  number = {3}
}

@article{miglio+2010,
  title = {Evidence for a Sharp Structure Variation inside a Red-Giant Star},
  author = {Miglio, A. and Montalb{\'a}n, J. and Carrier, F. and De Ridder, J. and Mosser, B. and Eggenberger, P. and Scuflaire, R. and Ventura, P. and D'Antona, F. and Noels, A. and Baglin, A.},
  year = {2010},
  month = sep,
  volume = {520},
  pages = {L6},
  issn = {0004-6361, 1432-0746},
  doi = {10.1051/0004-6361/201015442},
  abstract = {The availability of precisely determined frequencies of radial and non-radial oscillation modes in red giants is finally paving the way for detailed studies of the internal structure of these stars. We look for the seismic signature of regions of sharp structure variation in the internal structure of the CoRoT target HR7349. We analyse the frequency dependence of the large frequency separation and second frequency differences, as well as the behaviour of the large frequency separation obtained with the envelope auto-correlation function. We find evidence for a periodic component in the oscillation frequencies, i.e. the seismic signature of a sharp structure variation in HR7349. In a comparison with stellar models we interpret this feature as caused by a local depression of the sound speed that occurs in the helium second-ionization region. Using solely seismic constraints this allows us to estimate the mass (M=1.2\^\{+0.6\}\_\{-0.4\} Msun) and radius (R=12.2\^\{+2.1\}\_\{-1.8\} Rsun) of HR7349, which agrees with the location of the star in an HR diagram.},
  archivePrefix = {arXiv},
  eprint = {1009.1024},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/FKZAGQTV/Miglio et al. - 2010 - Evidence for a sharp structure variation inside a .pdf;/Users/Oliver/Zotero/storage/V3PBBMSS/1009.html},
  journal = {Astronomy and Astrophysics},
  keywords = {Astrophysics - Solar and Stellar Astrophysics}
}

@article{miglio+2012,
  title = {Asteroseismology of Old Open Clusters with {{Kepler}}: Direct Estimate of the Integrated Red Giant Branch Mass-Loss in {{NGC}} 6791 and 6819},
  shorttitle = {Asteroseismology of Old Open Clusters with {{Kepler}}},
  author = {Miglio, A. and Brogaard, K. and Stello, D. and Chaplin, W. J. and D'Antona, F. and Montalb{\'a}n, J. and Basu, S. and Bressan, A. and Grundahl, F. and Pinsonneault, M. and Serenelli, A. M. and Elsworth, Y. and Hekker, S. and Kallinger, T. and Mosser, B. and Ventura, P. and Bonanno, A. and Noels, A. and Silva Aguirre, V. and Szabo, R. and Li, J. and McCauliff, S. and Middour, C. K. and Kjeldsen, H.},
  year = {2012},
  month = jan,
  volume = {419},
  pages = {2077},
  doi = {10.1111/j.1365-2966.2011.19859.x},
  abstract = {Mass-loss of red giant branch (RGB) stars is still poorly determined, despite its crucial role in the chemical enrichment of galaxies. Thanks to the recent detection of solar-like oscillations in G-K giants in open clusters with Kepler, we can now directly determine stellar masses for a statistically significant sample of stars in the old open clusters NGC 6791 and 6819. The aim of this work is to constrain the integrated RGB mass-loss by comparing the average mass of stars in the red clump (RC) with that of stars in the low-luminosity portion of the RGB [i.e. stars with L{$\lessequivlnt$}L(RC)]. Stellar masses were determined by combining the available seismic parameters {$\nu$}\textsubscript{max} and {$\increment\nu$} with additional photometric constraints and with independent distance estimates. We measured the masses of 40 stars on the RGB and 19 in the RC of the old metal-rich cluster NGC 6791. We find that the difference between the average mass of RGB and RC stars is small, but significant [? (random) {$\pm$}0.04 (systematic) M\textsubscript{{$\Sun$}}]. Interestingly, such a small ? does not support scenarios of an extreme mass-loss for this metal-rich cluster. If we describe the mass-loss rate with Reimers prescription, a first comparison with isochrones suggests that the observed ? is compatible with a mass-loss efficiency parameter in the range 0.1 {$\lessequivlnt\eta\lessequivlnt$} 0.3. Less stringent constraints on the RGB mass-loss rate are set by the analysis of the{\~ }2 Gyr old NGC 6819, largely due to the lower mass-loss expected for this cluster, and to the lack of an independent and accurate distance determination. In the near future, additional constraints from frequencies of individual pulsation modes and spectroscopic effective temperatures will allow further stringent tests of the {$\increment\nu$} and {$\nu$}\textsubscript{max} scaling relations, which provide a novel, and potentially very accurate, means of determining stellar radii and masses.},
  file = {/Users/Oliver/Zotero/storage/YS6FPBW7/Miglio et al. - 2012 - Asteroseismology of old open clusters with Kepler.pdf;/Users/Oliver/Zotero/storage/WIIUVMZN/ui.adsabs.harvard.edu.html},
  journal = {Monthly Notices of the Royal Astronomical Society},
  language = {en},
  number = {3}
}

@article{miglio+2012a,
  title = {Asteroseismology of Old Open Clusters with {{Kepler}}: Direct Estimate of the Integrated Red Giant Branch Mass-Loss in {{NGC}} 6791 and 6819},
  shorttitle = {Asteroseismology of Old Open Clusters with {{Kepler}}},
  author = {Miglio, A. and Brogaard, K. and Stello, D. and Chaplin, W. J. and D'Antona, F. and Montalb{\'a}n, J. and Basu, S. and Bressan, A. and Grundahl, F. and Pinsonneault, M. and Serenelli, A. M. and Elsworth, Y. and Hekker, S. and Kallinger, T. and Mosser, B. and Ventura, P. and Bonanno, A. and Noels, A. and Silva Aguirre, V. and Szabo, R. and Li, J. and McCauliff, S. and Middour, C. K. and Kjeldsen, H.},
  year = {2012},
  month = jan,
  volume = {419},
  pages = {2077},
  doi = {10.1111/j.1365-2966.2011.19859.x},
  abstract = {Mass-loss of red giant branch (RGB) stars is still poorly determined, despite its crucial role in the chemical enrichment of galaxies. Thanks to the recent detection of solar-like oscillations in G-K giants in open clusters with Kepler, we can now directly determine stellar masses for a statistically significant sample of stars in the old open clusters NGC 6791 and 6819. The aim of this work is to constrain the integrated RGB mass-loss by comparing the average mass of stars in the red clump (RC) with that of stars in the low-luminosity portion of the RGB [i.e. stars with L{$\lessequivlnt$}L(RC)]. Stellar masses were determined by combining the available seismic parameters {$\nu$}\textsubscript{max} and {$\increment\nu$} with additional photometric constraints and with independent distance estimates. We measured the masses of 40 stars on the RGB and 19 in the RC of the old metal-rich cluster NGC 6791. We find that the difference between the average mass of RGB and RC stars is small, but significant [? (random) {$\pm$}0.04 (systematic) M\textsubscript{{$\Sun$}}]. Interestingly, such a small ? does not support scenarios of an extreme mass-loss for this metal-rich cluster. If we describe the mass-loss rate with Reimers prescription, a first comparison with isochrones suggests that the observed ? is compatible with a mass-loss efficiency parameter in the range 0.1 {$\lessequivlnt\eta\lessequivlnt$} 0.3. Less stringent constraints on the RGB mass-loss rate are set by the analysis of the{\~ }2 Gyr old NGC 6819, largely due to the lower mass-loss expected for this cluster, and to the lack of an independent and accurate distance determination. In the near future, additional constraints from frequencies of individual pulsation modes and spectroscopic effective temperatures will allow further stringent tests of the {$\increment\nu$} and {$\nu$}\textsubscript{max} scaling relations, which provide a novel, and potentially very accurate, means of determining stellar radii and masses.},
  file = {/Users/Oliver/Zotero/storage/ISBM8GWA/Miglio et al. - 2012 - Asteroseismology of old open clusters with Kepler.pdf;/Users/Oliver/Zotero/storage/T8NTZRFI/ui.adsabs.harvard.edu.html},
  journal = {Monthly Notices of the Royal Astronomical Society},
  language = {en},
  number = {3}
}

@article{miglio+2013,
  title = {Galactic Archaeology: Mapping and Dating Stellar Populations with Asteroseismology of Red-Giant Stars},
  shorttitle = {Galactic Archaeology},
  author = {Miglio, A. and Chiappini, C. and Morel, T. and Barbieri, M. and Chaplin, W. J. and Girardi, L. and Montalb{\'a}n, J. and Valentini, M. and Mosser, B. and Baudin, F. and Casagrande, L. and Fossati, L. and Silva Aguirre, V. and Baglin, A.},
  year = {2013},
  month = feb,
  volume = {429},
  pages = {423},
  doi = {10.1093/mnras/sts345},
  abstract = {Our understanding of how the Galaxy was formed and evolves is severely hampered by the lack of precise constraints on basic stellar properties such as distances, masses and ages. Here, we show that solar-like pulsating red giants represent a well-populated class of accurate distance indicators, spanning a large age range, which can be used to map and date the Galactic disc in the regions probed by observations made by the CoRoT and Kepler space telescopes. When combined with photometric constraints, the pulsation spectra of such evolved stars not only reveal their radii, and hence distances, but also provide well-constrained estimates of their masses, which are reliable proxies for the ages of the stars. As a first application, we consider red giants observed by CoRoT in two different parts of the Milky Way, and determine precise distances for{\~ }2000 stars spread across nearly 15 000 pc of the Galactic disc, exploring regions which are a long way from the solar neighbourhood. We find significant differences in the mass distributions of these two samples which, by comparison with predictions of synthetic models of the Milky Way, we interpret as mainly due to the vertical gradient in the distribution of stellar masses (hence ages) in the disc. In the future, the availability of spectroscopic constraints for this sample of stars will not only improve the age determination, but also provide crucial constraints on age-velocity and age-metallicity relations at different Galactocentric radii and heights from the plane.},
  file = {/Users/Oliver/Zotero/storage/HRSEZHAG/Miglio et al. - 2013 - Galactic archaeology mapping and dating stellar p.pdf;/Users/Oliver/Zotero/storage/MTUVCK8P/ui.adsabs.harvard.edu.html},
  journal = {Monthly Notices of the Royal Astronomical Society},
  language = {en},
  number = {1}
}

@article{miglio+2015,
  title = {Looks like a Duck, Moves like a Duck, but Does It Quack like a Duck? {{Asteroseismology}} of Red-Giant Stars in Clusters},
  shorttitle = {Looks like a Duck, Moves like a Duck, but Does It Quack like a Duck?},
  author = {Miglio, Andrea and Brogaard, Karsten and Handberg, Rasmus},
  year = {2015},
  month = aug,
  volume = {22},
  pages = {2251619},
  abstract = {Undoubtedly one the highlights of the Kepler asteroseismology programme has been the detection of solar-like oscillations in giants belonging to the open clusters NGC 6791, NGC 6819, and NGC 6811. The availability of such constraints has made it possible to infer precise stellar properties (e.g. radius, mass, evolutionary state, age) on a star-by-star basis.These constraints give us a ``new pair of eyes'' to look at clusters, and they open several exciting opportunities. Based on a detailed analysis of the complete set of 4-years-long Kepler data, we present clear evidence for stars that have undergone non-standard evolution (evolved blue stragglers, low-mass Li-rich stars). We then illustrate the potential of integrated-mass-loss and mass-loss-dispersion measurements in both NGC6791 and NGC6819, which suggest a small true mass scatter among the red-clump stars and thus a very small mass-loss dispersion.We will then show examples of how our analysis based on individual-mode frequencies, as opposed to average seismic parameters and scaling relations, allow us to determine with higher accuracy stellar properties, and to probe features in the deep stellar interior (i.e. acoustic glitches related to Helium ionisation, properties of near-core mixing in the He-core-burning phase).Finally, we will discuss the prospects for seismic analyses of other clusters, in particular the globular cluster M4 which could reveal new insights into mass-loss dispersion and its effect on the horizontal-branch morphology.},
  file = {/Users/Oliver/Zotero/storage/F8MQKU2G/ui.adsabs.harvard.edu.html},
  journal = {IAU General Assembly},
  language = {en}
}

@article{miglio+2015a,
  title = {Solar-{{Like Oscillating Stars}} as {{Standard Clocks}} and {{Rulers}} for {{Galactic Studies}}},
  author = {Miglio, Andrea and Girardi, L{\'e}o and Rodrigues, Tha{\'i}se S. and Stello, Dennis and Chaplin, William J.},
  year = {2015},
  volume = {39},
  pages = {11},
  doi = {10.1007/978-3-319-10993-0_2},
  abstract = {The CoRoT and Kepler space missions have detected oscillations in hundreds of Sun-like stars and thousands of field red-giant stars. This has opened the door to a new era of stellar population studies in the Milky Way. We report on the current status and future prospects of harvesting space-based photometric data for ensemble asteroseismology, and highlight some of the challenges that need to be faced to use these stars as accurate clocks and rulers for Galactic studies.},
  file = {/Users/Oliver/Zotero/storage/GPS2H3UG/ui.adsabs.harvard.edu.html},
  journal = {Asteroseismology of Stellar Populations in the Milky Way},
  language = {en}
}

@article{miglio+2016,
  title = {Detection of Solar-like Oscillations in Relics of the {{Milky Way}}: Asteroseismology of {{K}} Giants in {{M4}} Using Data from the {{NASA K2}} Mission},
  shorttitle = {Detection of Solar-like Oscillations in Relics of the {{Milky Way}}},
  author = {Miglio, A. and Chaplin, W. J. and Brogaard, K. and Lund, M. N. and Mosser, B. and Davies, G. R. and Handberg, R. and Milone, A. P. and Marino, A. F. and Bossini, D. and Elsworth, Y. P. and Grundahl, F. and Arentoft, T. and Bedin, L. R. and Campante, T. L. and {Jessen-Hansen}, J. and Jones, C. D. and Kuszlewicz, J. S. and Malavolta, L. and Nascimbeni, V. and Sandquist, E. L.},
  year = {2016},
  month = sep,
  volume = {461},
  pages = {760},
  doi = {10.1093/mnras/stw1555},
  abstract = {Asteroseismic constraints on K giants make it possible to infer radii, masses and ages of tens of thousands of field stars. Tests against independent estimates of these properties are however scarce, especially in the metal-poor regime. Here, we report the detection of solar-like oscillations in eight stars belonging to the red-giant branch (RGB) and red-horizontal branch (RHB) of the globular cluster M4. The detections were made in photometric observations from the K2 Mission during its Campaign 2. Making use of independent constraints on the distance, we estimate masses of the eight stars by utilizing different combinations of seismic and non-seismic inputs. When introducing a correction to the {$\increment\nu$} scaling relation as suggested by stellar models, for RGB stars we find excellent agreement with the expected masses from isochrone fitting, and with a distance modulus derived using independent methods. The offset with respect to independent masses is lower, or comparable with, the uncertainties on the average RGB mass (4-10 per cent, depending on the combination of constraints used). Our results lend confidence to asteroseismic masses in the metal-poor regime. We note that a larger sample will be needed to allow more stringent tests to be made of systematic uncertainties in all the observables (both seismic and non-seismic), and to explore the properties of RHB stars, and of different populations in the cluster.},
  file = {/Users/Oliver/Zotero/storage/LITNVE3G/Miglio et al. - 2016 - Detection of solar-like oscillations in relics of .pdf;/Users/Oliver/Zotero/storage/PMDN23WQ/ui.adsabs.harvard.edu.html},
  journal = {Monthly Notices of the Royal Astronomical Society},
  language = {en},
  number = {1}
}

@article{mints+hekker2017,
  title = {A {{Unified}} Tool to Estimate {{Distances}}, {{Ages}} and {{Masses}} ({{UniDAM}}) from Spectrophotometric Data},
  author = {Mints, Alexey and Hekker, Saskia},
  year = {2017},
  month = may,
  abstract = {Galactic archaeology - the study of the formation and evolution of the Milky Way by reconstructing its past from its current constituents - requires precise and accurate knowledge of stellar parameters for as many stars as possible. To achieve this a number of large spectroscopic surveys have been undertaken and are still ongoing. So far consortia carrying out the different spectroscopic surveys have used different tools to determine stellar parameters of stars from their derived effective temperatures (Teff), surface gravities (log g) and metallicities ([Fe/H]) possibly combined with photometric, astrometric, interferometric or asteroseismic information. Here we aim to homogenise the stellar characterisation by applying a unified tool to a large set of publicly available spectrophotometric data. We use spectroscopic data from a variety of large surveys combined with infra-red photometry from 2MASS and AllWISE and compare these in a Bayesian manner with PARSEC isochrones to derive probability density functions (PDFs) for stellar masses, ages and distances. We treat PDFs of pre-helium-core burning, helium-core burning and post helium-core burning solutions as well as different peaks in multi-modal PDFs (i.e. each unimodal sub-PDF) of the different evolutionary phases separately. For over 2.5 million stars we report mass, age and distance estimate for each evolutionary phase and unimodal sub-PDF. We report Gaussian, skewed Gaussian, truncated Gaussian, modified truncated exponential distribution or truncated Student's t-distribution functions to represent each sub-PDF, allowing to reconstruct detailed PDFs. Comparisons with stellar parameter estimates from the literature show good agreement within uncertainties. We present UniDAM - the unified tool applicable to spectrophotometric data of different surveys to obtain a homogenised set of stellar parameters.},
  archivePrefix = {arXiv},
  eprint = {1705.00963},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/5ZPT5IN8/Mints and Hekker - 2017 - A Unified tool to estimate Distances, Ages and Mas.pdf;/Users/Oliver/Zotero/storage/4QGD3PQI/1705.html},
  journal = {arXiv:1705.00963 [astro-ph]},
  keywords = {Astrophysics - Astrophysics of Galaxies,Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{mocnik+2017,
  title = {K2 {{Looks Towards WASP}}-28 and {{WASP}}-151},
  author = {Mo{\v c}nik, T. and Hellier, C. and Anderson, D. R.},
  year = {2017},
  month = oct,
  abstract = {By analysing the short-cadence K2 photometry from the observing Campaign 12 we refine the system parameters of hot Jupiter WASP-28b and hot Saturn WASP-151b. We report the non-detection and corresponding upper limits for transit-timing and transit-duration variations, starspots, rotational and phase-curve modulations and additional transiting planets. We discuss the cause of several background brightening events detected simultaneously in both planetary systems and conclude that they are likely associated with the passage of Mars across the field of view.},
  archivePrefix = {arXiv},
  eprint = {1710.08892},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/PUJKZQFF/Močnik et al. - 2017 - K2 Looks Towards WASP-28 and WASP-151.pdf;/Users/Oliver/Zotero/storage/HKSMUEK3/1710.html},
  journal = {arXiv:1710.08892 [astro-ph]},
  keywords = {Astrophysics - Earth and Planetary Astrophysics},
  primaryClass = {astro-ph}
}

@article{molnar+2016,
  title = {Variable Stars with the {{Kepler}} Space Telescope},
  author = {Moln{\'a}r, L{\'a}szl{\'o} and Szab{\'o}, R{\'o}bert and Plachy, Emese},
  year = {2016},
  month = oct,
  volume = {1610},
  pages = {arXiv:1610.02004},
  abstract = {The Kepler space telescope has revolutionised our knowledge about exoplanets and stars and is continuing to do so in the K2 mission. The exquisite photometric precision, together with the long, uninterrupted observations opened up a new way to investigate the structure and evolution of stars. Asteroseismology, the study of stellar oscillations, allowed us to investigate solar-like stars and to peer into the insides of red giants and massive stars. But many discoveries have been made about classical variable stars too, ranging from pulsators like Cepheids and RR Lyraes to eclipsing binary stars and cataclysmic variables, and even supernovae. In this review, which is far from an exhaustive summary of all results obtained with Kepler, we collected some of the most interesting discoveries, and ponder on the role for amateur observers in this golden era of stellar astrophysics.},
  journal = {ArXiv e-prints},
  keywords = {Astrophysics - Instrumentation and Methods for Astrophysics,Astrophysics - Solar and Stellar Astrophysics}
}

@article{molnar+2018,
  title = {Gaia {{Data Release}} 2: {{Validation}} of the Classification of {{RR Lyrae}} and {{Cepheid}} Variables with the {{Kepler}} and {{K2}} Missions},
  shorttitle = {Gaia {{Data Release}} 2},
  author = {Moln{\'a}r, L{\'a}szl{\'o} and Plachy, Emese and Juh{\'a}sz, {\'A}ron L. and Rimoldini, Lorenzo},
  year = {2018},
  month = may,
  abstract = {The second data release of the Gaia mission includes an advance catalog of variable stars. The classification of these stars are based on sparse photometry from the first 22 months of the mission. We set out to investigate the purity and completeness of the all-sky Gaia classification results with the help of the continuous light curves of the observed targets from the Kepler and K2 missions, focusing specifically on RR Lyrae and Cepheid pulsators, outside the Galactic Bulge region. We crossmatched the Gaia identifications with the observations collected by the Kepler space telescope. We inspected the light curves visually, then calculated the relative Fourier coefficients and period ratios for the single- and double-mode K2 RR Lyrae stars to further classify them. We identified 1443 and 41 stars classified as RR Lyrae or Cepheid variables in DR2 in the targeted observations of the two missions and 263 more RR Lyre targets in the Full-Frame Images (FFI) of the original mission and provide the crossmatch of these sources. We conclude that the RR Lyrae catalog has a completeness between 70-78\%, and provide a purity estimate between 92-98\% (targeted observations) with lower limits of 75\% (FFI stars) and 51\% (K2 worst-case scenario). The low number of Cepheids prevents us from drawing detailed conclusions but the purity of the DR2 sample is estimated to be around 66\%.},
  archivePrefix = {arXiv},
  eprint = {1805.11395},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/IXUC5988/Molnár et al. - 2018 - Gaia Data Release 2 Validation of the classificat.pdf;/Users/Oliver/Zotero/storage/RNSXDRZN/1805.html},
  journal = {arXiv:1805.11395 [astro-ph]},
  keywords = {Astrophysics - Solar and Stellar Astrophysics},
  primaryClass = {astro-ph}
}

@article{montalban+2010,
  title = {Seismic {{Diagnostics}} of {{Red Giants}}: {{First Comparison}} with {{Stellar Models}}},
  shorttitle = {Seismic {{Diagnostics}} of {{Red Giants}}},
  author = {Montalb{\'a}n, J. and Miglio, A. and Noels, A. and Scuflaire, R. and Ventura, P.},
  year = {2010},
  month = oct,
  volume = {721},
  pages = {L182},
  doi = {10.1088/2041-8205/721/2/L182},
  abstract = {The clear detection with CoRoT and KEPLER of radial and non-radial solar-like oscillations in many red giants paves the way for seismic inferences on the structure of such stars. We present an overview of the properties of the adiabatic frequencies and frequency separations of radial and non-radial oscillation modes for an extended grid of models. We highlight how their detection allows a deeper insight into the internal structure and evolutionary state of red giants. In particular, we find that the properties of dipole modes constitute a promising seismic diagnostic tool of the evolutionary state of red giant stars. We compare our theoretical predictions with the first 34 days of KEPLER data and predict the frequency diagram expected for red giants in the CoRoT exofield in the galactic center direction.},
  file = {/Users/Oliver/Zotero/storage/848D3HGR/Montalbán et al. - 2010 - Seismic Diagnostics of Red Giants First Compariso.pdf;/Users/Oliver/Zotero/storage/UCM5ADRS/ui.adsabs.harvard.edu.html},
  journal = {The Astrophysical Journal},
  language = {en},
  number = {2}
}

@article{mosser+2010,
  title = {Red-Giant Seismic Properties Analyzed with {{CoRoT}}},
  author = {Mosser, B. and Belkacem, K. and Goupil, M. J. and Miglio, A. and Morel, T. and Barban, C. and Baudin, F. and Hekker, S. and Samadi, R. and De Ridder, J. and Weiss, W. and Auvergne, M. and Baglin, A.},
  year = {2010},
  month = jul,
  volume = {517},
  pages = {A22},
  issn = {0004-6361, 1432-0746},
  doi = {10.1051/0004-6361/201014036},
  abstract = {The CoRoT 5-month long observation runs give us the opportunity to analyze a large variety of red-giant stars and to derive fundamental stellar parameters from their asteroseismic properties. We perform an analysis of more than 4\textbackslash,600 CoRoT light curves to extract as much information as possible. We take into account the characteristics of the star sample and of the method in order to provide asteroseismic results as unbiased as possible. We also study and compare the properties of red giants of two opposite regions of the Galaxy. We analyze the time series with the envelope autocorrelation function in order to extract precise asteroseismic parameters with reliable error bars. We examine first the mean large frequency separation of solar-like oscillations and the frequency of maximum seismic amplitude, then the parameters of the excess power envelope. With the additional information of the effective temperature, we derive the stellar mass and radius. We have identified more than 1\textbackslash,800 red giants among the 4\textbackslash,600 light curves and have obtained accurate distributions of the stellar parameters for about 930 targets. We were able to reliably measure the mass and radius of several hundred red giants. We have derived precise information on the stellar population distribution and on the red clump. Comparison between the stars observed in two different fields shows that the stellar asteroseismic properties are globally similar, but with different characteristics for red-clump stars. This study shows the efficiency of statistical asteroseismology: validating scaling relations allows us to infer fundamental stellar parameters, to derive precise information on the red-giant evolution and interior structure and to analyze and compare stellar populations from different fields.},
  archivePrefix = {arXiv},
  eprint = {1004.0449},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/CA5TC5GJ/Mosser et al. - 2010 - Red-giant seismic properties analyzed with CoRoT.pdf;/Users/Oliver/Zotero/storage/ZK3XSW8C/1004.html},
  journal = {Astronomy and Astrophysics},
  keywords = {Astrophysics - Solar and Stellar Astrophysics}
}

@article{mosser+2011,
  title = {Mixed Modes in Red-Giant Stars Observed with {{CoRoT}}},
  author = {Mosser, B. and Barban, C. and Montalb{\'a}n, J. and Beck, P. G. and Miglio, A. and Belkacem, K. and Goupil, M. J. and Hekker, S. and De Ridder, J. and Dupret, M. A. and Elsworth, Y. and Noels, A. and Baudin, F. and Michel, E. and Samadi, R. and Auvergne, M. and Baglin, A. and Catala, C.},
  year = {2011},
  month = aug,
  volume = {532},
  pages = {A86},
  doi = {10.1051/0004-6361/201116825},
  abstract = {Context. The CoRoT mission has provided thousands of red-giant light curves. The analysis of their solar-like oscillations allows us to characterize their stellar properties. \\
 Aims: Up to now, the global seismic parameters of the pressure modes have been unable to distinguish red-clump giants from members of the red-giant branch. As recently done with Kepler red giants, we intend to analyze and use the so-called mixed modes to determine the evolutionary status of the red giants observed with CoRoT. We also aim at deriving different seismic characteristics depending on evolution. \\
 Methods: The complete identification of the pressure eigenmodes provided by the red-giant universal oscillation pattern allows us to aim at the mixed modes surrounding the {$\mathscr{l}$} = 1 expected eigenfrequencies. A dedicated method based on the envelope autocorrelation function is proposed to analyze their period separation. \\
 Results: We have identified the mixed-mode signature separation thanks to their pattern that is compatible with the asymptotic law of gravity modes. We have shown that, independent of any modeling, the g-mode spacings help to distinguish the evolutionary status of a red-giant star. We then report the different seismic and fundamental properties of the stars, depending on their evolutionary status. In particular, we show that high-mass stars of the secondary clump present very specific seismic properties. We emphasize that stars belonging to the clump were affected by significant mass loss. We also note significant population and/or evolution differences in the different fields observed by CoRoT. The CoRoT space mission, launched 2006 December 27, was developed and is operated by the CNES, with participation of the Science Programs of ESA, ESA\v{S}s RSSD, Austria, Belgium, Brazil, Germany, and Spain.Apeendix A is available in electronic form at \href{http://www.aanda.org}{http://www.aanda.org}},
  file = {/Users/Oliver/Zotero/storage/8IL7L879/Mosser et al. - 2011 - Mixed modes in red-giant stars observed with CoRoT.pdf;/Users/Oliver/Zotero/storage/QHRLU92T/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en}
}

@article{mosser+2012,
  title = {Characterization of the Power Excess of Solar-like Oscillations in Red Giants with {{Kepler}}},
  author = {Mosser, B. and Elsworth, Y. and Hekker, S. and Huber, D. and Kallinger, T. and Mathur, S. and Belkacem, K. and Goupil, M. J. and Samadi, R. and Barban, C. and Bedding, T. R. and Chaplin, W. J. and Garc{\'i}a, R. A. and Stello, D. and De Ridder, J. and Middour, C. K. and Morris, R. L. and Quintana, E. V.},
  year = {2012},
  month = jan,
  volume = {537},
  pages = {A30},
  doi = {10.1051/0004-6361/201117352},
  abstract = {Context. The space mission Kepler provides us with long and uninterrupted photometric time series of red giants. This allows us to examine their seismic global properties and to compare these with theoretical predictions. \\
 Aims: We aim to describe the oscillation power excess observed in red giant oscillation spectra with global seismic parameters, and to investigate empirical scaling relations governing these parameters. From these scalings relations, we derive new physical properties of red giant oscillations. \\
 Methods: Various different methods were compared in order to validate the processes and to derive reliable output values. For consistency, a single method was then used to determine scaling relations for the relevant global asteroseismic parameters: mean mode height, mean height of the background signal superimposed on the oscillation power excess, width of the power excess, bolometric amplitude of the radial modes and visibility of non-radial modes. A method for deriving oscillation amplitudes is proposed, which relies on the complete identification of the red giant oscillation spectrum. \\
 Results: The comparison of the different methods has shown the important role of the way the background is modelled. The convergence reached by the collaborative work enables us to derive significant results concerning the oscillation power excess. We obtain several scaling relations, and identify the influence of the stellar mass and the evolutionary status. The effect of helium burning on the red giant interior structure is confirmed: it yields a strong mass-radius relation for clump stars. We find that none of the amplitude scaling relations motivated by physical considerations predict the observed mode amplitudes of red giant stars. In parallel, the degree-dependent mode visibility exhibits important variations. Both effects seem related to the significant influence of the high mode mass of non-radial mixed modes. A family of red giants with very weak dipole modes is identified, and its properties are analyzed. \\
 Conclusions: The clear correlation between the power densities of the background signal and of the stellar oscillation induces important consequences to be considered for deriving a reliable theoretical relation of the mode amplitude. As a by-product of this work, we have verified that red giant asteroseismology delivers new insights for stellar and Galactic physics, given the evidence for mass loss at the tip of the red giant branch. Appendices are available in electronic form at \href{http://www.aanda.org}{http://www.aanda.org}},
  file = {/Users/Oliver/Zotero/storage/TTMANT7W/Mosser et al. - 2012 - Characterization of the power excess of solar-like.pdf;/Users/Oliver/Zotero/storage/GN8XATIS/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en}
}

@article{mosser+2012a,
  title = {Probing the Core Structure and Evolution of Red Giants Using Gravity-Dominated Mixed Modes Observed with {{Kepler}}},
  author = {Mosser, B. and Goupil, M. J. and Belkacem, K. and Michel, E. and Stello, D. and Marques, J. P. and Elsworth, Y. and Barban, C. and Beck, P. G. and Bedding, T. R. and De Ridder, J. and Garc{\'i}a, R. A. and Hekker, S. and Kallinger, T. and Samadi, R. and Stumpe, M. C. and Barclay, T. and Burke, C. J.},
  year = {2012},
  month = apr,
  volume = {540},
  pages = {A143},
  doi = {10.1051/0004-6361/201118519},
  abstract = {Context. There are now more than 22 months of long-cadence data available for thousands of red giants observed with the Kepler space mission. Consequently, we are able to clearly resolve fine details in their oscillation spectra and see many components of the mixed modes that probe the stellar core. \\
 Aims: We report for the first time a parametric fit to the pattern of the {$\mathscr{l}$} = 1 mixed modes in red giants, which is a powerful tool to identify gravity-dominated mixed modes. With these modes, which share the characteristics of pressure and gravity modes, we are able to probe directly the helium core and the surrounding shell where hydrogen is burning. \\
 Methods: We propose two ways for describing the so-called mode bumping that affects the frequencies of the mixed modes. Firstly, a phenomenological approach is used to describe the main features of the mode bumping. Alternatively, a quasi-asymptotic mixed-mode relation provides a powerful link between seismic observations and the stellar interior structure. We used period \'echelle diagrams to emphasize the detection of the gravity-dominated mixed modes. \\
 Results: The asymptotic relation for mixed modes is confirmed. It allows us to measure the gravity-mode period spacings in more than two hundred red giant stars. The identification of the gravity-dominated mixed modes allows us to complete the identification of all major peaks in a red giant oscillation spectrum, with significant consequences for the true identification of {$\mathscr{l}$} = 3 modes, of {$\mathscr{l}$} = 2 mixed modes, for the mode widths and amplitudes, and for the {$\mathscr{l}$} = 1 rotational splittings. \\
 Conclusions: The accurate measurement of the gravity-mode period spacing provides an effective probe of the inner, g-mode cavity. The derived value of the coupling coefficient between the cavities is different for red giant branch and clump stars. This provides a probe of the hydrogen-shell burning region that surrounds the helium core. Core contraction as red giants ascend the red giant branch can be explored using the variation of the gravity-mode spacing as a function of the mean large separation. Full version of Table 1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via \href{http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/540/A143}{http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/540/A143}},
  file = {/Users/Oliver/Zotero/storage/HKDVY55K/Mosser et al. - 2012 - Probing the core structure and evolution of red gi.pdf;/Users/Oliver/Zotero/storage/6FVCBW6D/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en}
}

@article{mosser+2012b,
  title = {Spin down of the Core Rotation in Red Giants},
  author = {Mosser, B. and Goupil, M. J. and Belkacem, K. and Marques, J. P. and Beck, P. G. and Bloemen, S. and De Ridder, J. and Barban, C. and Deheuvels, S. and Elsworth, Y. and Hekker, S. and Kallinger, T. and Ouazzani, R. M. and Pinsonneault, M. and Samadi, R. and Stello, D. and Garc{\'i}a, R. A. and Klaus, T. C. and Li, J. and Mathur, S. and Morris, R. L.},
  year = {2012},
  month = dec,
  volume = {548},
  pages = {A10},
  doi = {10.1051/0004-6361/201220106},
  abstract = {Context. The space mission Kepler provides us with long and uninterrupted photometric time series of red giants. We are now able to probe the rotational behaviour in their deep interiors using the observations of mixed modes. \\
 Aims: We aim to measure the rotational splittings in red giants and to derive scaling relations for rotation related to seismic and fundamental stellar parameters. \\
 Methods: We have developed a dedicated method for automated measurements of the rotational splittings in a large number of red giants. Ensemble asteroseismology, namely the examination of a large number of red giants at different stages of their evolution, allows us to derive global information on stellar evolution. \\
 Results: We have measured rotational splittings in a sample of about 300 red giants. We have also shown that these splittings are dominated by the core rotation. Under the assumption that a linear analysis can provide the rotational splitting, we observe a small increase of the core rotation of stars ascending the red giant branch. Alternatively, an important slow down is observed for red-clump stars compared to the red giant branch. We also show that, at fixed stellar radius, the specific angular momentum increases with increasing stellar mass. \\
 Conclusions: Ensemble asteroseismology indicates what has been indirectly suspected for a while: our interpretation of the observed rotational splittings leads to the conclusion that the mean core rotation significantly slows down during the red giant phase. The slow-down occurs in the last stages of the red giant branch. This spinning down explains, for instance, the long rotation periods measured in white dwarfs. Appendices A and B are available in electronic form at \href{http://www.aanda.org}{http://www.aanda.org}},
  file = {/Users/Oliver/Zotero/storage/R8W3GG3I/Mosser et al. - 2012 - Spin down of the core rotation in red giants.pdf;/Users/Oliver/Zotero/storage/4LHWZP57/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en}
}

@article{mosser+2013,
  title = {Asymptotic and Measured Large Frequency Separations},
  author = {Mosser, B. and Michel, E. and Belkacem, K. and Goupil, M. J. and Baglin, A. and Barban, C. and Provost, J. and Samadi, R. and Auvergne, M. and Catala, C.},
  year = {2013},
  month = feb,
  volume = {550},
  pages = {A126},
  issn = {0004-6361, 1432-0746},
  doi = {10.1051/0004-6361/201220435},
  abstract = {With the space-borne missions CoRoT and Kepler, a large amount of asteroseismic data is now available. So-called global oscillation parameters are inferred to characterize the large sets of stars, to perform ensemble asteroseismology, and to derive scaling relations. The mean large separation is such a key parameter. It is therefore crucial to measure it with the highest accuracy. As the conditions of measurement of the large separation do not coincide with its theoretical definition, we revisit the asymptotic expressions used for analysing the observed oscillation spectra. Then, we examine the consequence of the difference between the observed and asymptotic values of the mean large separation. The analysis is focused on radial modes. We use series of radial-mode frequencies to compare the asymptotic and observational values of the large separation. We propose a simple formulation to correct the observed value of the large separation and then derive its asymptotic counterpart. We prove that, apart from glitches due to stellar structure discontinuities, the asymptotic expansion is valid from main-sequence stars to red giants. Our model shows that the asymptotic offset is close to 1/4, as in the theoretical development. High-quality solar-like oscillation spectra derived from precise photometric measurements are definitely better described with the second-order asymptotic expansion. The second-order term is responsible for the curvature observed in the \textbackslash 'echelle diagrams used for analysing the oscillation spectra and this curvature is responsible for the difference between the observed and asymptotic values of the large separation. Taking it into account yields a revision of the scaling relations providing more accurate asteroseismic estimates of the stellar mass and radius.},
  archivePrefix = {arXiv},
  eprint = {1212.1687},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/W2Z28J3H/Mosser et al. - 2013 - Asymptotic and measured large frequency separation.pdf;/Users/Oliver/Zotero/storage/ZCFW2HPV/1212.html},
  journal = {Astronomy \& Astrophysics},
  keywords = {Astrophysics - Solar and Stellar Astrophysics}
}

@article{mosser+2015,
  title = {Period Spacings in Red Giants. {{I}}. {{Disentangling}} Rotation and Revealing Core Structure Discontinuities},
  author = {Mosser, B. and Vrard, M. and Belkacem, K. and Deheuvels, S. and Goupil, M. J.},
  year = {2015},
  month = dec,
  volume = {584},
  pages = {A50},
  doi = {10.1051/0004-6361/201527075},
  abstract = {Context. Asteroseismology allows us to probe the physical conditions inside the core of red giant stars. This process relies on the properties of the global oscillations with a mixed character that are highly sensitive to the physical properties of the core. However, overlapping rotational splittings and mixed-mode spacings result in complex structures in the mixed-mode pattern, which severely complicates its identification and the measurement of the asymptotic period spacing. \\
 Aims: This work aims at disentangling the rotational splittings from the mixed-mode spacings in order to open the way to a fully automated analysis of large data sets. \\
 Methods: An analytical development of the mixed-mode asymptotic expansion is used to derive the period spacing between two consecutive mixed modes. The \'echelle diagrams constructed with the appropriately stretched periods are used to exhibit the structure of the gravity modes and of the rotational splittings. \\
 Results: We propose a new view of the mixed-mode oscillation pattern based on corrected periods, called stretched periods, that mimic the evenly spaced gravity-mode pattern. This provides a direct understanding of all oscillation components, even in the case of rapid rotation. In this way, the measurement of the asymptotic period spacing and the signature of the structural glitches on mixed modes can be performed easily. \\
 Conclusions: This work makes it possible to derive all seismic global parameters in an automated way, including the identification of the different rotational multiplets and the measurement of the rotational splitting, even when this splitting is significantly larger than the period spacing. Revealing buoyancy glitches provides a detailed view of the radiative core.},
  file = {/Users/Oliver/Zotero/storage/S78ZUWWV/Mosser et al. - 2015 - Period spacings in red giants. I. Disentangling ro.pdf;/Users/Oliver/Zotero/storage/MDYFZDXL/ui.adsabs.harvard.edu.html},
  journal = {Astronomy and Astrophysics},
  language = {en}
}

@article{mosser+appourchaux2009,
  title = {On Detecting the Large Separation in the Autocorrelation of Stellar Oscillation Times Series},
  author = {Mosser, B. and Appourchaux, T.},
  year = {2009},
  month = dec,
  volume = {508},
  pages = {877},
  doi = {10.1051/0004-6361/200912944},
  abstract = {Context: The observations carried out by the space missions CoRoT and Kepler provide a large set of asteroseismic data. Their analysis requires an efficient procedure first to determine if a star reliably shows solar-like oscillations, second to measure the so-called large separation, third to estimate the asteroseismic information that can be retrieved from the Fourier spectrum.\\
 Aims: In this paper we develop a procedure based on the autocorrelation of the seismic Fourier spectrum that is capable of providing measurements of the large and small frequency separations. The performance of the autocorrelation method needs to be assessed and quantified. We therefore searched for criteria able to predict the output that one can expect from the analysis by autocorrelation of a seismic time series. \\
 Methods: First, the autocorrelation is properly scaled to take into account the contribution of white noise. Then we use the null hypothesis H\textsubscript{0} test to assess the reliability of the autocorrelation analysis. Calculations based on solar and CoRoT time series are performed to quantify the performance as a function of the amplitude of the autocorrelation signal.\\
 Results: We obtain an empirical relation for the performance of the autocorrelation method. We show that the precision of the method increases with the observation length, and with the mean seismic amplitude-to-background ratio of the pressure modes to the power 1.5 {$\pm$} 0.05. We propose an automated determination of the large separation, whose reliability is quantified by the H\textsubscript{0} test. We apply this method to analyze red giants observed by CoRoT. We estimate the expected performance for photometric time series of the Kepler mission. We demonstrate that the method makes it possible to distinguish {$\mathscr{l}$} = 0 from {$\mathscr{l}$} = 1 modes.\\
 Conclusions: The envelope autocorrelation function (EACF) has proven to be very powerful for the determination of the large separation in noisy asteroseismic data, since it enables us to quantify the precision of the performance of different measurements: mean large separation, variation of the large separation with frequency, small separation and degree identification. The CoRoT space mission, launched on 2006 December 27, was developed and is operated by the CNES, with participation of the Science Programs of ESA, ESA's RSSD, Austria, Belgium, Brazil, Germany and Spain.},
  file = {/Users/Oliver/Zotero/storage/LYJF5KQ3/Mosser and Appourchaux - 2009 - On detecting the large separation in the autocorre.pdf;/Users/Oliver/Zotero/storage/MG36QMF7/abstract.html},
  journal = {Astronomy and Astrophysics},
  language = {en},
  number = {2}
}

@incollection{mosser+miglio2016,
  title = {{{IV}}.2 {{Pulsating}} Red Giant Stars: {{Ensemble}} Asteroseismology and {{Asteroseismology}} of Stellar Populations in the {{Milky}} Way},
  shorttitle = {{{IV}}.2 {{Pulsating}} Red Giant Stars},
  booktitle = {The {{CoRoT Legacy Book}}},
  author = {Mosser, B. and Miglio, A.},
  editor = {{CoRot Team} and Baglin, Annie},
  year = {2016},
  pages = {197},
  publisher = {{EDP Sciences}},
  doi = {10.1051/978-2-7598-1876-1.c042},
  file = {/Users/Oliver/Zotero/storage/SF6AD7ZJ/Mosser and Miglio - 2016 - IV.2 Pulsating red giant stars Ensemble asterosei.pdf},
  isbn = {978-2-7598-1876-1},
  language = {en}
}

@misc{mosser2016,
  title = {Period Spacings in Red Giants --- {{III}}. {{Coupling}} Factors of Mixed Modes},
  author = {Mosser, B},
  year = {2016},
  file = {/Users/Oliver/Zotero/storage/RPHWZ4GQ/Mosser_et_al_2016.pdf}
}

@article{moya+2018,
  title = {The Asteroseismic Potential of {{CHEOPS}}},
  author = {Moya, A. and Forteza, S. Barcel{\'o} and Bonfanti, A. and Salmon, S. J. A. J. and Van Grootel, V. and Barrado, D.},
  year = {2018},
  month = dec,
  volume = {620},
  pages = {A203},
  issn = {0004-6361, 1432-0746},
  doi = {10.1051/0004-6361/201833772},
  abstract = {Asteroseismology has been impressively boosted during the last decade mainly thanks to space missions such as Kepler/K2 and CoRoT. This has a large impact, in particular, in exoplanetary sciences since the accurate characterization of the exoplanets is convoluted in most cases with the characterization of their hosting star. Until the expected launch of the ESA mission PLATO 2.0, there is almost a decade where only two important missions will provide short-cadence high-precision photometric time-series: NASA--TESS and ESA--CHEOPS missions, both having high capabilities for exoplanetary sciences. In this work, we want to explore the asteroseismic potential of CHEOPS time-series. Following the works done for estimating the asteroseismic potential of Kepler and TESS, we have analyzed the probability of detecting solar-like pulsations using CHEOPS light-curves. Since CHEOPS will collect runs with observational times from hours up to a few days, we have analyzed the accuracy and precision we can obtain for the estimation of nu\_max, the only asteroseismic observable we can recover using CHEOPS observations. Finally, we have analyzed the impact of knowing nu\_max in the characterization of exoplanet host stars. Using CHEOPS light-curves with the expected observational times we can determine nu\_max for massive G and F-type stars from late Main Sequence on, and for F, G, and K-type stars from post-Main Sequence on with an uncertainty lower than a 5\%. For magnitudes V{$<$}12 and observational times from eight hours up to two days, the HR zone of potential detectability changes. The determination of nu\_max leads to an internal age uncertainty reduction in the characterization of exoplanet host stars from 52\% to 38\%; mass uncertainty reduction from 2.1\% to 1.8\%; radius uncertainty reduction from 1.8\% to 1.6\%; density uncertainty reduction from 5.6\% to 4.7\%, in our best scenarios.},
  archivePrefix = {arXiv},
  eprint = {1811.01573},
  eprinttype = {arxiv},
  file = {/Users/Oliver/Zotero/storage/2PQNB7FV/Moya et al. - 2018 - The asteroseismic potential of CHEOPS.pdf;/Users/Oliver/Zotero/storage/G7FFBQKS/1811.html},
  journal = {Astronomy \& Astrophysics},
  keywords = {Astrophysics - Earth and Planetary Astrophysics,Astrophysics - Solar and Stellar Astrophysics}
}

@article{moya+2018a,
  title = {Empirical {{Relations}} for the {{Accurate Estimation}} of {{Stellar Masses}} and {{Radii}}},
  author = {Moya, Andy and Zuccarino, Federico and Chaplin, William J. and Davies, Guy R.},
  year = {2018},
  month = aug,
  volume = {237},
  pages = {21},
  doi = {10.3847/1538-4365/aacdae},
  abstract = {In this work, we have taken advantage of the most recent accurate stellar characterizations carried out using asteroseismology, eclipsing binaries and interferometry to evaluate a comprehensive set of empirical relations for the estimation of stellar masses and radii. We have gathered a total of 934 stars\textemdash of which around two-thirds are on the main sequence\textemdash that are characterized with different levels of precision, most of them having estimates of M, R, T \textsubscript{eff}, L, g, {$\rho$}, and [Fe/H]. We have deliberately used a heterogeneous sample (in terms of characterizing techniques and spectroscopic types) to reduce the influence of possible biases coming from the observation, reduction, and analysis methods used to obtain the stellar parameters. We have studied a total of 576 linear combinations of T \textsubscript{eff}, L, g, {$\rho$}, and [Fe/H] (and their logarithms) to be used as independent variables to estimate M or R. We have used an error-in-variables linear regression algorithm to extract the relations and to ensure the fair treatment of the uncertainties. We present a total of 38 new or revised relations that have an adj-R \textsuperscript{2} regression statistic higher than 0.85, and a relative accuracy and precision better than 10\% for almost all the cases. The relations cover almost all the possible combinations of observables, ensuring that, whatever list of observables is available, there is at least one relation for estimating the stellar mass and radius.},
  file = {/Users/Oliver/Zotero/storage/C8TXETR9/Moya et al. - 2018 - Empirical Relations for the Accurate Estimation of.pdf;/Users/Oliver/Zotero/storage/P4IGXRTX/abstract.html},
  journal = {The Astrophysical Journal Supplement Series},
  language = {en},
  number = {2}
}

@article{mullally+2015,
  title = {Planetary {{Candidates Observed}} by {{Kepler}}. {{VI}}. {{Planet Sample}} from {{Q1}}--{{Q16}} (47 {{Months}})},
  author = {Mullally, F. and Coughlin, Jeffrey L. and Thompson, Susan E. and Rowe, Jason and Burke, Christopher and Latham, David W. and Batalha, Natalie M. and Bryson, Stephen T. and Christiansen, Jessie and Henze, Christopher E. and Ofir, Aviv and Quarles, Billy and Shporer, Avi and Van Eylen, Vincent and Van Laerhoven, Christa and Shah, Yash and Wolfgang, Angie and Chaplin, W. J. and Xie, Ji-Wei and Akeson, Rachel and Argabright, Vic and Bachtell, Eric and Barclay, Thomas and Borucki, William J. and Caldwell, Douglas A. and Campbell, Jennifer R. and Catanzarite, Joseph H. and Cochran, William D. and Duren, Riley M. and Fleming, Scott W. and Fraquelli, Dorothy and Girouard, Forrest R. and Haas, Michael R. and He{\l}miniak, Krzysztof G. and Howell, Steve B. and Huber, Daniel and Larson, Kipp and Gautier, III, Thomas N. and Jenkins, Jon M. and Li, Jie and Lissauer, Jack J. and McArthur, Scot and Miller, Chris and Morris, Robert L. and {Patil-Sabale}, Anima and Plavchan, Peter and Putnam, Dustin and Quintana, Elisa V. and Ramirez, Solange and Silva Aguirre, V. and Seader, Shawn and Smith, Jeffrey C. and Steffen, Jason H. and Stewart, Chris and Stober, Jeremy and Still, Martin and Tenenbaum, Peter and Troeltzsch, John and Twicken, Joseph D. and Zamudio, Khadeejah A.},
  year = {2015},
  month = apr,
  volume = {217},
  pages = {31},
  issn = {0067-0049},
  doi = {10.1088/0067-0049/217/2/31},
  abstract = {We present the sixth catalog of Kepler candidate planets based on nearly
four years of high precision photometry. This catalog builds on the
legacy of previous catalogs released by the Kepler project and includes
1493 new Kepler Objects of Interest (KOIs) of which 554 are planet
candidates, and 131 of these candidates have best-fit radii \textbackslash lt 1.5
\{\{R\}\textbackslash oplus \}. This brings the total number of KOIs and planet
candidates to 7348 and 4175 respectively. We suspect that many of these
new candidates at the low signal-to-noise ratio limit may be false
alarms created by instrumental noise, and discuss our efforts to
identify such objects. We re-evaluate all previously published KOIs with
orbital periods of \textbackslash gt 50 days to provide a consistently vetted sample
that can be used to improve planet occurrence rate calculations. We
discuss the performance of our planet detection algorithms, and the
consistency of our vetting products. The full catalog is publicly
available at the NASA Exoplanet Archive.},
  file = {/Users/Oliver/Zotero/storage/E72X3QHQ/Mullally et al. - 2015 - Planetary Candidates Observed by Kepler. VI. Plane.pdf},
  journal = {The Astrophysical Journal Supplement Series},
  keywords = {catalogs,eclipses,planetary systems}
}

@article{murphy+2013,
  title = {Super-{{Nyquist Asteroseismology}} with the {{Kepler Space Telescope}}*},
  author = {Murphy, S. J. and Shibahashi, H. and Kurtz, D. W.},
  year = {2013},
  month = dec,
  volume = {479},
  pages = {517},
  abstract = {Barycentric corrections made to the timing of Kepler observations,
necessitated by variations in light arrival time at the satellite, break
the  regular time sampling of the data - the time stamps are
periodically modulated.  A consequence is that Nyquist aliases are split
into multiplets that can be  identified by their shape. Real pulsation
frequencies are distinguishable from  these aliases and their
frequencies are completely recoverable, even in the  super-Nyquist
regime, that is, when the sampling interval is longer than half  the
pulsation period. We provide an analytical derivation of the phenomenon,
alongside demonstrations with simulated and real Kepler data for
{$\delta$} Sct, roAp, and sdBV stars. For Kepler data sets spanning more
than one Kepler orbital period (372.5 d), there are no Nyquist
ambiguities in the determination of pulsation frequencies, which are the
fundamental data of asteroseismology.},
  file = {/Users/Oliver/Zotero/storage/Q7N732GI/Murphy et al. - 2013 - Super-Nyquist Asteroseismology with the Kepler Spa.pdf}
}

@article{ness+2015,
  title = {The {{Cannon}}: {{A}} Data-Driven Approach to {{Stellar Label Determination}}},
  shorttitle = {The {{Cannon}}},
  author = {Ness, M. and Hogg, David W. and Rix, H.-W. and Ho, Anna Y. Q. and Zasowski, G.},
  year = {2015},
  month = jul,
  volume = {808},
  pages = {16},
  issn = {0004-637X},
  doi = {10.1088/0004-637X/808/1/16},
  abstract = {New spectroscopic surveys offer the promise of stellar parameters and abundances (``stellar labels'') for hundreds of thousands of stars; this poses a formidable spectral modeling challenge. In many cases, there is a subset of reference objects for which the stellar labels are known with high(er) fidelity. We take advantage of this with The Cannon

license: MIT

license_type: permissive

branch_name: refs/heads/master

extension: bib