Astronomy and Astrophysics – Astrophysics
Scientific paper
Jan 2003
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003a%26a...397..147p&link_type=abstract
Astronomy and Astrophysics, v.397, p.147-157 (2003)
Astronomy and Astrophysics
Astrophysics
215
Stars: Activity, Stars: Late-Type, X-Rays: Stars
Scientific paper
We present the results of a new study on the relationship between coronal X-ray emission and stellar rotation in late-type main-sequence stars. We have selected a sample of 259 dwarfs in the B-V range 0.5-2.0, including 110 field stars and 149 members of the Pleiades, Hyades, alpha Persei, IC 2602 and IC 2391 open clusters. All the stars have been observed with ROSAT, and most of them have photometrically-measured rotation periods available. Our results confirm that two emission regimes exist, one in which the rotation period is a good predictor of the total X-ray luminosity, and the other in which a constant saturated X-ray to bolometric luminosity ratio is attained; we present a quantitative estimate of the critical rotation periods below which stars of different masses (or spectral types) enter the saturated regime. In this work we have also empirically derived a characteristic time scale, taue , which we have used to investigate the relationship between the X-ray emission level and an X-ray-based Rossby number Re = Prot/taue: we show that our empirical time scale taue resembles the theoretical convective turnover time for 0.4 <~ M/Msun <~ 1.2, but it also has the same functional dependence on B-V as Lbol-1/2 in the color range 0.5 <~ B-V <~ 1.5. Our results imply that - for non-saturated coronae - the Lx - Prot relation is equivalent to the Lx/Lbol vs. Re relation. Tables 1 and 2 are only available in electronic form at \ http://www.edpsciences.org
Maggio Antonio
Micela Giuseppina
Pizzolato Nicola
Sciortino Salvatore
Ventura Paolo
No associations
LandOfFree
The stellar activity-rotation relationship revisited: Dependence of saturated and non-saturated X-ray emission regimes on stellar mass for late-type dwarfs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The stellar activity-rotation relationship revisited: Dependence of saturated and non-saturated X-ray emission regimes on stellar mass for late-type dwarfs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The stellar activity-rotation relationship revisited: Dependence of saturated and non-saturated X-ray emission regimes on stellar mass for late-type dwarfs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1524196