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Title: Extending the Asteroseismic Calibration of the Stellar Rossby Number
Abstract The stellar Rossby number (Ro) is a dimensionless quantity that is used in the description of fluid flows. It characterizes the relative importance of Coriolis forces on convective motions, which is central to understanding magnetic stellar evolution. Here we present an expanded sample of Kepler asteroseismic targets to help calibrate the relation between Ro and Gaia color, and we extend the relation to redder colors using observations of the mean activity levels and rotation periods for a sample of brighter stars from the Mount Wilson survey. Our quadratic fit to the combined sample is nearly linear between 0.55 < GBP − GRP < 1.2, and can be used to estimate Ro for stars with spectral types between F5 and K3. The strong deviation from linearity in the original calibration may reflect an observational bias against the detection of solar-like oscillations at higher activity levels for the coolest stars.  more » « less
Award ID(s):
2205888
PAR ID:
10613352
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Research Notes of the American Astronomical Society
Date Published:
Journal Name:
Research Notes of the AAS
Volume:
8
Issue:
10
ISSN:
2515-5172
Page Range / eLocation ID:
260
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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