Submitted to Ap J L Gas Density, Stability and Starbursts Near the Inner Lindblad Resonance of the Milky Way

• Main Authors: Antony A. Stark, Christopher L. Martin, Wilfred M. Walsh, Kecheng Xiao, Adair P. Lane, Christopher K. Walker
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2004
• Subjects: Subject headings; Galaxy; structure—ISM; clouds—ISM; molecules—galaxies; Antarctic; The Antarctic; Milky Way; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.337.5674; http://arxiv.org/pdf/astro-ph/0405330v1.pdf

A key project of the Antarctic Submillimeter Telescope and Remote Observatory reported by Martin et al. (2004) is the mapping of CO J = 4 → 3 and J = 7 → 6 emission from the inner Milky Way, allowing determination of gas density and temperature. Galactic center gas that Binney et al. (1991) identify as being on x2 orbits has a density near 10 3.5 cm −3, which renders it only marginally stable against gravitational coagulation into a few Giant Molecular Clouds, as discussed by Elmegreen (1994). This suggests a relaxation oscillator mechanism for starbursts in the Milky Way, where inflowing gas accumulates in a ring at 150 pc radius for approximately 20 million years, until the critical density is reached, and the resulting instability leads to the sudden formation of giant clouds and the deposition of 4 × 10 7 M ⊙ of gas onto the Galactic center.