Characterising molecular gas in nearby star forming galaxies
Abstract
Regions of very dense, star-forming gas in the interstellar medium are necessary to maintain star formation activity in hostile conditions. Star-forming regions in these environments are able to resist winds and radiative forces from newly formed stars longer than gas in the surrounding ISM. Subject to a proper interpretation, observations of molecules can be used for many purposes: tracing the reservoir or leftover of the star formation process; tracing the process of star formation itself; and determining the galaxy energetics through influence of newly-formed stars or an AGN on their environments. We map the distribution of several tracer molecules over three nearby galaxies. We begin by mapping two starburst galaxies with single dish observations of the dense gas tracer CS. The formation of CS is modelled under different conditions with results fed into a molecular line radiative transfer model. From this we can obtain the physical conditions of the regions of the ISM where there is a high rate of star-formation, as well as compare how the conditions vary away from the galactic centre. Moving on from here, we use ALMA to map NGC 1068. Observations of several molecules across the AGN and starburst regions are used to determine conditions and processes with a spatial resolution of less than 35 parsecs.
- Publication:
-
IAU General Assembly
- Pub Date:
- August 2015
- Bibcode:
- 2015IAUGA..2257626K