Kinematic Identification of Young Nearby Moving Groups from a Sample of Chromospherically Active Stars in the Rave Catalog

Wednesday, 13 June 2018 8 a.m. — 9 a.m. MST

AURA Lecture Hall

NOIRLab South Colloquia
VALERIA RAMIREZ (Instituto de Astronomia de la UNAM, Ensenada,México and Magister Invited by Universidad de La Serena and CTIO)

The goal of this study is to identify groups of young stars through their kinematics. For this purpose we present a kinematic analysis for a sample of chromospherically active stars in the RAVE catalog (Kunder et al. 2017).

A large percentage of the RAVE sources with evidence of chromospheric activity (approximately 14000), also present signatures of stellar youth (Žerjal et al. 2013). We selected a sample of sources with the highest probability of chromospheric activity to look for common kinematics. We developed a purely kinematic method that allows the detection of young nearby moving groups candidates in the sample. We detected a set of regions with significant density in the 3D velocity orientation space, representing groups of stars with common movement. We determined the statistical significance of the overdensities with respect to averaged artificial distributions made from a purely Gaussian velocity ellipsoid with null vertex deviation. After this analysis, we compared this sample of highly significant stars with a catalog of young nearby moving groups reported in previous studies (M. Rodriguez et al. in prep). With this comparison we found at least 77 members already confirmed of known moving groups and more than 600 possible candidates for new groups.