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arXiv · 2006.06204

Rotation of solar analogs cross-matching Kepler and Gaia DR2

Jose-Dias do Nascimento Jr·Leandro de Almeida·Eduardo Nunes Velloso·Francys Anthony·Sydney A Barnes·Steven H Saar·Soren Meibom·Jefferson Soares da Costa·Matthieu Castro·Jhon Yana Galarza·Diego Lorenzo-Oliveira·Paul G. Beck·Jorge Melendez
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Abstract

A major obstacle to interpreting the rotation period distribution for main-sequence stars from Kepler mission data has been the lack of precise evolutionary status for these objects. We address this by investigating the evolutionary status based on Gaia Data Release 2 parallaxes and photometry for more than 30,000 Kepler stars with rotation period measurements. Many of these are subgiants, and should be excluded in future work on dwarfs. We particularly investigate a 193-star sample of solar analogs, and report newly-determined rotation periods for 125 of these. These include 54 stars from a prior sample, of which can confirm the periods for 50. The remainder are new, and 10 of them longer than solar rotation period, suggesting that sun-like stars continue to spin down on the main sequence past solar age. Our sample of solar analogs could potentially serve as a benchmark for future missions such as PLATO, and emphasizes the need for additional astrometric, photometric, and spectroscopic information before interpreting the stellar populations and results from time-series surveys.

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Jose-Dias do Nascimento Jr, Leandro de Almeida, Eduardo Nunes Velloso, Francys Anthony, Sydney A Barnes, Steven H Saar, Soren Meibom, Jefferson Soares da Costa, Matthieu Castro, Jhon Yana Galarza, Diego Lorenzo-Oliveira, Paul G. Beck, Jorge Melendez. 2020-06-11. Rotation of solar analogs cross-matching Kepler and Gaia DR2. https://doi.org/10.3847/1538-4357/ab9c16

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