The long bar as seen by the VVV survey: I. Colour-magnitude diagrams

• Main Authors: González-Fernández, C, López-Corredoira, M, Amôres, E. B, Minniti, D, Lucas, P, Toledo, I
• Format: Journal Article
• Language: English
• Published: 27-09-2012
• Subjects: Physics - Astrophysics of Galaxies
• DOI: 10.48550/arxiv.1209.4370

The VISTA Variable Survey (VVV) is able to map the Galaxy at l<0 with an
unpaired depth (at least 3 mag deeper than 2MASS), opening new possibilities
for studying the inner structure of the Milky Way. In this paper we concentrate
on the exploitation of these data to better understand the spatial disposition
and distribution of the structures present in the inner Milky Way, particularly
the Long Bar and its interaction with the inner disc.
The observations show the presence of a clear overdensity of stars with
associated recent stellar formation that we interpret as the traces of the Long
Bar, and we derive an angle for it of 41+/-5 with the Sun-Galactic centre line,
touching the disc near l=27 and l=-12. The colour-magnitude diagrams presented
here also show a lack of disc stars in several lines of sight, a fact that we
associate with the truncation of the disc by the potential of this bar for
Galactocentric radius less than 5kpc.