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 (
We present a study of the relationship between Galactic kinematics, flare rates, chromospheric activity, and rotation periods for a volume-complete, nearly all-sky sample of 219 single stars within 15 pc and with masses between 0.1 and 0.3
- PAR ID:
- 10369743
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 935
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 104
- Size(s):
- Article No. 104
- Sponsoring Org:
- National Science Foundation
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Abstract P rot) for 220 ≲1.3M ⊙ Praesepe members and recovery periods for 97% (793/812) of the stars with aP rot in the literature. Of the 19 stars for which we do not recover aP rot, 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 measuredP rot for stars observed in more than one campaign. We measureP rot consistent to within 10% for >95% of the 331 likely single stars with ≥2 high-quality observations; the median difference inP rot is 0.3%, with a standard deviation of 2%. Nearly all of the exceptions are stars with discrepantP rot 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,P rot measurements for low-mass stars in Praesepe are stable on timescales of several years. AP rot can therefore be taken to be representative even if measured only once. -
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