Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 17 октября 2017 г.
Аннотация:We use stellar proper motions from the TGAS catalog to study thekinematics of OB-associations. The TGAS proper motions ofOB-associations generally agree well with the Hipparcos propermotions. The parameters of the Galactic rotation curve obtainedwith TGAS and Hipparcos proper motions agree within the errors.The average one-dimensional velocity dispersion inside 18OB-associations with more than 10 TGAS stars is sigma_v=3.9 kms-1, which is considerably smaller, by a factor of 0.4, thanthe velocity dispersions derived from Hipparcos data. Theeffective contribution from orbital motions of binary OB-starsinto the velocity dispersion sigma_v inside OB-associations issigma_b=1.2$ km s-1. The median virial and stellar massesof OB-associations are equal to 7.1 10^5 and 9.0 10^3Ms, respectively. Thus OB-associations must be unboundobjects provided they do not include a lot of dense gas. Themedian star-formation efficiency is epsilon=2.1 percent. Nearlyone third of stars of OB-associations must lie outside their tidalradius. We found that the Per OB1 and Car OB1 associations areexpanding with the expansion started in a small region of 11--27pc 7--10 Myr ago. The average expansion velocity is 6.3 kms-1.