Monoceros OB4: a new association in Gaia DR2

TY - JOUR

T1 - Monoceros OB4

T2 - a new association in Gaia DR2

AU - Teixeira, Paula Stella

AU - Alves, João

AU - Sicilia-Aguilar, Aurora

AU - Hacar, Alvaro

AU - Scholz, Alexander

N1 - Copyright: © 2021 Oxford University Press. All rights reserved.

PY - 2021/3/31

Y1 - 2021/3/31

N2 - We use Gaia DR2 data to survey the classic Monoceros OB1 region and look for the existence of a dispersed young population, co-moving with the cloud complex. An analysis of the distribution of proper motions reveals a 20-30 Myr association of young stars, about 300-400 pc away from the far side of the Mon OB1 complex, along the same general line-of-sight. We characterize the new association, Monoceros OB4, and estimate it contains between 1400 and 2500 stars, assuming a standard IMF, putting it on par in size with NGC\,2264. We find from the internal proper motions that Mon OB4 is unbound and expanding. Our results seem to unveil a larger and more complex Monoceros star formation region, suggesting an elongated arrangement that seems to be at least 300 x 60 pc.

AB - We use Gaia DR2 data to survey the classic Monoceros OB1 region and look for the existence of a dispersed young population, co-moving with the cloud complex. An analysis of the distribution of proper motions reveals a 20-30 Myr association of young stars, about 300-400 pc away from the far side of the Mon OB1 complex, along the same general line-of-sight. We characterize the new association, Monoceros OB4, and estimate it contains between 1400 and 2500 stars, assuming a standard IMF, putting it on par in size with NGC\,2264. We find from the internal proper motions that Mon OB4 is unbound and expanding. Our results seem to unveil a larger and more complex Monoceros star formation region, suggesting an elongated arrangement that seems to be at least 300 x 60 pc.

KW - ISM: individual objects: Monoceros OB1 cloud complex

KW - Stars: pre-main sequence

KW - Galaxy: open clusters and association: general

UR - https://www.scopus.com/pages/publications/85127048375

U2 - 10.1093/mnrasl/slab029

DO - 10.1093/mnrasl/slab029

M3 - Article

AN - SCOPUS:85127048375

SN - 1745-3925

VL - 504

SP - L17-L21

JO - Monthly Notices of the Royal Astronomical Society: Letters

JF - Monthly Notices of the Royal Astronomical Society: Letters

IS - 1

ER -