DISTRIBUIÇÃO DE VELOCIDADES ROTACIONAIS EM 4 AGLOMERADOS ABERTOS NA REGIÃO DE CARINA

Abstract

Abstract DISTRIBUTIONS OF PROJECTED ROTATIONAL VELOCITIES IN 4 OPEN CLUSTERS IN THE CARINA REGION Wilton de Jesús Santos August/2018 Advisor: PhD. Simone Daflon Program: Astronomy Trumpler 14, 15 and 16 (Tr14, Tr15 and Tr16) and Collinder 228 (Coll228) are very young open clusters located in the Carina Nebula. Tr14 and Tr16 present very high concentration of massive and luminous stars and are the riches clusters in the Carina region. These OB stars exhibit high values of projected rotational velocity (Vsin i), typically > ~150 km/s, which may induce changes in their evolution. In this work, we determined the stellar vsin(i) from the widths of HeI lines measured from the observed spectra and interpolated in a grid of widths measured from non-LTE synthetic spectra. The stars have been assigned to the 4 clusters based on previous membership studies from the literature and considering our measurements of radial velocities and proper motions from Gaia DR2. We obtained the vsin(i) distributions for each of the 4 clusters in the Carina region and analyzed the distributions in terms of the clusters parameters.