논문 상세보기
pp.31-52
The rotational properties of late-type main sequence stars in the solar neighborhood have been investigated. So rotation periods and stellar radii are determined for 104 field stars, 8 Ursa Major Group stars, and 20 Hyades cluster stars. Most of the rotation periods are derived using the Noyes et al. (1984)'s relation between chromospheric activity and rotation period. Stellar radii are calculated by the Stefan law for the nearby stars within 25 pc from the sun. Rotational velocities at equator are determined by the above rotation periods and stellar radii. Their distribution along the (B-V) color shows an upper boundary and an abrupt drop for the stars in the range of 0.4<(B-V)<0.8, as found from the apparent rotational velocity data. Furthermore, it is apparent that there is an lower boundary of rotational velocity. The inclination of rotation axis to line-of-sight is obtained by comparing the rotational velocity at equator with the apparent rotational velocity given by the analysis of the line profiles. For the field stars, it is found that the inclination has no correlation with the galactic lattitude and follows random distribution.
