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arXiv · 1810.03338

CARMENES input catalogue of M dwarfs IV. New rotation periods from photometric time series

Abstract

Aims. The main goal of this work is to measure rotation periods of the M-type dwarf stars being observed by the CARMENES exoplanet survey to help distinguish radial-velocity signals produced by magnetic activity from those produced by exoplanets. Rotation periods are also fundamental for a detailed study of the relation between activity and rotation in late-type stars. Methods. We look for significant periodic signals in 622 photometric time series of 337 bright, nearby M dwarfs obtained by long-time baseline, automated surveys (MEarth, ASAS, SuperWASP, NSVS, Catalina, ASAS-SN, K2, and HATNet) and for 20 stars which we obtained with four 0.2-0.8 m telescopes at high geographical latitudes. Results. We present 142 rotation periods (73 new) from 0.12 d to 133 d and ten long-term activity cycles (six new) from 3.0 a to 11.5 a. We compare our determinations with those in the existing literature; we investigate the distribution of P rot in the CARMENES input catalogue,the amplitude of photometric variability, and their relation to vsin i and pEW(Halfa); and we identify three very active stars with new rotation periods between 0.34 d and 23.6 d.

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E. Diez Alonso, J. A. Caballero, D. Montes, F. J. de Cos Juez, S. Dreizler, F. Dubois, S. V. Jeffers, S. Lalitha, R. Naves, A. Reiners, I. Ribas, S. Vanaverbeke, P. J. Amado, V. J. S. Bejar, M. Cortes-Contreras, E. Herrero, D. Hidalgo, M. Kurster, L. Logie, A. Quirrenbach, S. Rau, W. Seifert, P. Schofer, L. Tal-Or. 2018-10-08. CARMENES input catalogue of M dwarfs IV. New rotation periods from photometric time series. https://doi.org/10.1051/0004-6361%2F201833316

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