Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-04-25
Mon.Not.Roy.Astron.Soc. 316 (2000) 950
Astronomy and Astrophysics
Astrophysics
Accepted by MNRAS
Scientific paper
10.1046/j.1365-8711.2000.03625.x
We present high resolution spectroscopy of a sample of 24 solar-type stars in the young (15-40 Myr), open cluster, NGC 2547. We use our spectra to confirm cluster membership in 23 of these stars, determine projected equatorial velocities and chromospheric activity, and to search for the presence of accretion discs. We have found examples of both fast (vsini>50kms) and slow (vsini<10kms) rotators, but find no evidence for active accretion in any of the sample. The distribution of projected rotation velocities is indistinguishable from the slightly older IC 2391 and IC 2602 clusters, implying similar initial angular momentum distributions and circumstellar disc lifetimes. The presence of very slow rotators indicates that either long (10-40 Myr) disc lifetimes or internal differential rotation are needed, or that NGC 2547 (and IC 2391/2602) were born with more slowly rotating stars than are presently seen in even younger clusters and associations. The solar-type stars in NGC 2547 follow a similar rotation-activity relationship to that seen in older clusters. X-ray activity increases until a saturation level is reached for vsini>15-20kms. We are unable to explain why this saturation level, of log (L_x/L_bol)~-3.3, is a factor of two lower than in other clusters, but rule out anomalously slow rotation rates or uncertainties in X-ray flux calculations.
James David J.
Jeffries Robin D.
Totten Edward J.
No associations
LandOfFree
Rotation and activity in the solar-type stars of NGC 2547 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 Rotation and activity in the solar-type stars of NGC 2547, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotation and activity in the solar-type stars of NGC 2547 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-473434