RotationActivity Correlations in K and M Dwarfs. I. Stellar Parameters and Compilations of v sin I and P/sin I for a Large Sample of LateK and M Dwarfs
Abstract
The reliable determination of rotationactivity correlations (RACs) depends on precise measurements of the following stellar parameters: T _{eff}, parallax, radius, metallicity, and rotational speed v sin I. In this paper, our goal is to focus on the determination of these parameters for a sample of K and M dwarfs. In a future paper (Paper II), we will combine our rotational data with activity data in order to construct RACs. Here, we report on a determination of effective temperatures based on the (RI)_{ C } color from the calibrations of Mann et al. and Kenyon & Hartmann for four samples of lateK, dM2, dM3, and dM4 stars. We also determine stellar parameters (T _{eff}, log(g), and [M/H]) using the principal component analysisbased inversion technique for a sample of 105 lateK dwarfs. We compile all effective temperatures from the literature for this sample. We determine empirical radius[M/H] correlations in our stellar samples. This allows us to propose new effective temperatures, stellar radii, and metallicities for a large sample of 612 lateK and M dwarfs. Our mean radii agree well with those of Boyajian et al. We analyze HARPS and SOPHIE spectra of 105 lateK dwarfs, and we have detected v sin I in 92 stars. In combination with our previous v sin I measurements in M and K dwarfs, we now derive P/sin I measures for a sample of 418 K and M dwarfs. We investigate the distributions of P/sin I, and we show that they are different from one spectral subtype to another at a 99.9% confidence level.
Based on observations available at Observatoire de Haute Provence and the European Southern Observatory databases and on Hipparcos parallax measurements.
 Publication:

The Astrophysical Journal
 Pub Date:
 May 2016
 DOI:
 10.3847/0004637X/822/2/97
 arXiv:
 arXiv:1604.07920
 Bibcode:
 2016ApJ...822...97H
 Keywords:

 stars: fundamental parameters;
 stars: latetype;
 stars: rotation;
 Astrophysics  Solar and Stellar Astrophysics
 EPrint:
 51 pages, 15 Figures, 7 Tables