Abstract

Poster - Splinter General   (Kuppelsaal / virtual plenum)

Exploring HI and OH in the Milky Way with the DSA-2000

Michael Rugel
DZA/NRAO

The physical processes and conditions governing the formation of molecular clouds out of the diffuse interstellar medium (ISM) are key to our understanding of galaxy evolution. Observational constraints on the involved atomic and molecular gas phases, in particular unknown components such as the CO-dark gas, are crucial to describe the molecular cloud formation process in different galaxy environments. The next-generation telescope DSA-2000, a novel interferometer of up to 2000 small aperture antennas planned by the California Institute of Technology on a remote site in Nevada, USA, will provide the sensitivity and survey speed for decisive contributions to answering these questions. With respect to the ISM in the Milky Way, the DSA-2000 will have the unique capability to observe the HI 21 cm line at unprecedented surface brightness sensitivity and high angular resolution to map the warm and cold interstellar medium, as well as the ultra-cold HI in molecular clouds. Its large collecting area will be ideally suited for potentially simultaneous deep Galaxy-wide OH 1667 MHz absorption observations to search for CO-dark gas. Our poster will outline survey characteristics, strategies and challenges of potential HI and OH observations with the DSA-2000.