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Title: Three K2 Campaigns Yield Rotation Periods for 1013 Stars in Praesepe
Abstract We use three campaigns of K2 observations to complete the census of rotation in low-mass members of the benchmark, ≈670 Myr old open cluster Praesepe. We measure new rotation periods (Prot) for 220 ≲1.3 M⊙ Praesepe members and recovery periods for 97% (793/812) of the stars with aProt in the literature. Of the 19 stars for which we do not recover a Prot, 17 were not observed by K2. As K2’s three Praesepe campaigns took place over the course of 3 yr, we test the stability of our measured Prot for stars observed in more than one campaign. We measure Prot consistent to within 10% for >95% of the 331 likely single stars with ≥2 high-quality observations; the median difference in Prot is 0.3%, with a standard deviation of 2%. Nearly all of the exceptions are stars with discrepant Prot measurements in Campaign 18, K2’s last, which was significantly shorter than the earlier two (≈50 days rather than ≈75 days). This suggests that, despite the evident morphological evolution we observe in the light curves of 38% of the stars, Prot measurements for low-mass stars in Praesepe are stable on timescales of several years. A Prot can therefore be taken to be representative even if measured only once.  more » « less
Award ID(s):
2009840
PAR ID:
10555976
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Astronomical Society/IOP
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
921
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
167
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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