Michael Rugel (Germany)
rugel @ mpia.de
Global properties of atomic and molecular gas in the interstellar medium with the THOR survey
What are the global properties of the atomic and molecular gas in the Milky Way with respect to different environments, e.g. galactic latitude, galactocentric distance or the presence of HII regions? To address these questions, as part of the THOR project (THOR - The HI, OH, Recombination Line survey of the Milky Way), we map four OH hyperfine transitions (1612, 1665, 1667 and 1720 MHz) and the HI 21 cm line in the northern part of the Milky Way (l = 15◦ − 67◦, |b| ≤ 1◦). This survey allows for an investigation of the interstellar medium in its atomic and molecular gas on unprecedented angular resolution of ~20 arcseconds over a large part of the galaxy. In my first project, I investigate the absorption in the OH 1665 MHz transition and the HI 21 cm line against galactic and extragalactic continuum sources. We determine kinematic properties, optical depth profiles and column densities for each source of absortpion. We compare turbulent properties in molecular and atomic gas among each other and against extragalactic and galactic continuum sources. We will compare
the results with other large scale surveys, especially with surveys in CO emission, in order to understand the relation between OH absorption and absorption in other molecular tracers.
Supervisor: Henrik Beuther (MPIA)