The β Pictoris association low-mass members: Membership assessment, rotation period distribution, and dependence on multiplicity

LANZAFAME, A.C.; BUCCINO, A.; MESSINA, S.; MILLWARD, M.; DESIDERA, S.; ARTEMENKO, S.; MALO, L.; ZHANG, L.; HAMBSCH, F.-J.

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Año: 2017 vol. 607

0004-6361

Context. Low-mass members of young loose stellar associations and open clusters exhibit a wide spread of rotation periods. Such a spread originates from the distributions of masses and initial rotation periods. However, multiplicity can also play a significant role. Aims. We aim to investigate the role played by physical companions in multiple systems in shortening the primordial disk lifetime, anticipating the rotation spin up with respect to single stars. Methods. We have compiled the most extensive list to date of low-mass bona fide and candidate members of the young 25-Myr β Pictoris association. We have measured from our own photometric time series or from archival time series the rotation periods of almost all members. In a few cases the rotation periods were retrieved from the literature. We used updated UVWXYZ components to assess the membership of the whole stellar sample. Thanks to the known basic properties of most members we built the rotation period distribution distinguishing between bona fide members and candidate members and according to their multiplicity status. Results. We find that single stars and components of multiple systems in wide orbits (>80 AU) have rotation periods that exhibit a well defined sequence arising from mass distribution with some level of spread likely arising from initial rotation period distribution. All components of multiple systems in close orbits (