2001/10/22 by C. Alard · 2 citations
Arts and Humanities · Medicine · Physics and Astronomy · Social Sciences · #American Sports and Literature #Earthquake and Disaster Impact Studies #Legal Cases and Commentary #astro-ph
paper · pdf · doi:10.1051/0004-6361:20011487
Accepted for publication in A&A Letters
arxiv created 2001/10/22 · openalex publication_date 2001/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
A map of the projected density of the old stellar population of the Galactic Bulge region is reconstructed using 2MASS data. By making a combination of the H and K photometric bands, it is possible to overcome the effect of reddening, and thus penetrate the inner structure of the Galactic Bulge. The main structure in the map corresponds to the well documented peanut shaped bar which is formed by the inner parts of the Galactic disk as a result of dynamical instabilities. As suggested by numerical simulations, the projected Z profile of the bar, has an almost exponential shape. After subtracting the exponential profile associated with the bar, a large residual appear near the Galactic Center. This residual is elongated and asymmetrical, which suggest a bar structure. Thus we arrive at the conclusion that in addition to the main bar a smaller bar with a different orientation may exist in the central region of the Milky Way. This finding makes the Milky Way very similar to a large number of barred spiral Galaxies which show as well a smaller bar in their central regions.