The Long Bar in the Milky Way: Corroboration of an Old Hypothesis
Abstract
Recent Galactic Legacy Infrared Mid-Plane Survey Extraordinaire data have further confirmed the hypothesis of the existence of an in-plane long bar different from the bulge of the Milky Way with the same characteristics as emphasized some years ago by our team. In this paper we present two new analyses that corroborate recent and earlier claims concerning the existence in our Galaxy of a long, flat bar with approximate dimensions of 7.8 kpc×1.2 kpc×0.2 kpc and a position angle of approximately 43°: (1) star counts with 2MASS All-Sky Data Release and Midcourse Space Experiment data, which give an excess in the plane region along 0deg<l<30deg compared with -30deg<l<0deg that cannot be due to the bulge, spiral arms, a ring, or extinction; and (2) new data on the distance of the long bar using the red clump method, together with recent observations of our own that are compared with our model and that are in agreement with the long-bar scenario.
- Publication:
-
The Astronomical Journal
- Pub Date:
- January 2007
- DOI:
- 10.1086/509605
- arXiv:
- arXiv:astro-ph/0606201
- Bibcode:
- 2007AJ....133..154L
- Keywords:
-
- Galaxy: structure;
- infrared: stars;
- Astrophysics
- E-Print:
- 22 pages, 7 figures, accepted in AJ. We thank the GLIMPSE team for the re-discovery of the long bar we had found some years ago, although we would be more satisfied if they cited our papers too. V3: two new (not very important) sections added about the other parameters of the bar and the low contamination of the bulge