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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

Gettysburg College

Series

Star rotation

Publication Year

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

New Rotation Periods In The Pleiades: Interpreting Activity Indicators, Anita Krishnamurthi, D. M. Terndrup, M. H. Pinsonneault, K. Sellgren, John R. Stauffer, Rudolph Schild, D. E. Backman, K. B. Beisser, D. B. Dahari, Amil Dasgupta, J. T. Hagelgans, M. A. Seeds, Rajan Anand '98, Bentley D. Laaksonen '95, Laurence A. Marschall, T. Ramseyer Jan 1998

New Rotation Periods In The Pleiades: Interpreting Activity Indicators, Anita Krishnamurthi, D. M. Terndrup, M. H. Pinsonneault, K. Sellgren, John R. Stauffer, Rudolph Schild, D. E. Backman, K. B. Beisser, D. B. Dahari, Amil Dasgupta, J. T. Hagelgans, M. A. Seeds, Rajan Anand '98, Bentley D. Laaksonen '95, Laurence A. Marschall, T. Ramseyer

Physics and Astronomy Faculty Publications

We present results of photometric monitoring campaigns of G, K and M dwarfs in the Pleiades carried out in 1994, 1995 and 1996. We have determined rotation periods for 18 stars in this cluster. In this paper, we examine the validity of using observables such as X-ray activity and amplitude of photometric variations as indicators of angular momentum loss. We report the discovery of cool, slow rotators with high amplitudes of variation. This contradicts previous conclusions about the use of amplitudes as an alternate diagnostic of the saturation of angular momentum loss. We show that the X-ray data can be …


Rotational Periods And Starspot Activity Of Young Solar-Type Dwarfs In The Open Cluster Ic 4665, S. Allain, C. Prosser, Laurence A. Marschall, Bentley D. Laaksonen Jan 1996

Rotational Periods And Starspot Activity Of Young Solar-Type Dwarfs In The Open Cluster Ic 4665, S. Allain, C. Prosser, Laurence A. Marschall, Bentley D. Laaksonen

Physics and Astronomy Faculty Publications

We present the results of a V-band photometric monitoring survey of 15 late-type dwarfs in the young open cluster IC 4665. Low-amplitude periodic light variations are found for 8 stars and ascribed to the modulation by starspots that cover typically a few percent of the stellar disk. Periods range from 0.6 to 3.7d, translating to equatorial velocities between 13 and 93 km.s-1. That no period longer than 4d was detected suggests a relative paucity of extremely slow rotators (Veq << 10 km.s-1) among late-type dwarfs in IC 4665. The fractional number of slow rotators in IC 4665 is similar to that of Alpha Per cluster, suggesting that IC 4665 is close in age to Alpha Per (~50 Myr).