Astrophysics Luncheon Seminar
The Energy Balance of the ISM in M31. [CII] Emission as a SFR Tracer
Presented by Maria Kapala
University of Cape Town, South Africa; Max Planck Institute for Astronomy, Germany
Monday, October 26, 2015
12:00 noon in 169-336
The energy balance sets the structure of the interstellar medium (ISM) phases, which in turn control the processes of star-formation (SF). Understanding the energy balance of the ISM is an essential step towards understanding the processes which shape evolution of galaxies across the cosmic time, and lead to the diversity of galaxy properties in the Universe. This work focuses on M31, an ideal laboratory to study the ISM due to its proximity, external perspective, and as it is a representative of the large, star-forming, metal-rich galaxies where most of the SF in the local Universe occurs. I will present the Survey of Lines in M31 (SLIM) with contributing new Integral Field Spectroscopic Herschel [CII] and Calar Alto Halpha data, which allow us to study the dominant neutral gas coolant - [CII] on ~50pc scales. I combine archival ISO [CII] measurements in the bulge of M31 with ancillary data to identify potential heating sources responsible for gas heating in the absence of young stars. For the first time in extragalactic studies, I directly constrain the ISRF intensity and spectral shape, based on PHAT modelling of the spectral energy distributions (SEDs) and extinction of the individual stars in M31 from the PHAT.
JPL Contact: Jorge Pineda (4-3347)