William Langer


The GOT C+ [CII] 158µm Survey of the Inner 1 kpc of the Galaxy

T. Velusamy, J. L. Pineda, K. Willacy, P.F. Goldsmith


Here we discuss new information on the structure and dynamics of the Interstellar Medium (ISM) in the inner 1 kpc of the Galaxy, based on data from the Herschel Open Time Key Project, Galactic Observations of Terahertz C+ (GOT C+), a survey of [CII] throughout the Galaxy. Here we present [CII] position-velocity maps that reveal the distribution and motion of the clouds in the inner 1 kpc of the Milky Way. We also discuss more detailed results on the physical properties of the gas in the inner Galaxy using spectral observations of HI, 12CO(1−0), 13CO(1−0), 12CO(3−2), and in some cases [CI], to supplement the [CII] data. With these tracers we identify and characterize the physical properties of the [CII] clouds using excitation and cloud chemical models. We will discuss these results and their constraints on the pressure, temperature, density, FUV intensity, and “Dark H2 Gas” fraction of these clouds. Our quantitative results provide a template for external galaxies using [CII] as a probe of the warm, dense ISM. This research was conducted at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration.