New Views of Warm Molecular Gas in Nearby Galaxies

Kamenetzky Julia, Boulder CO

Investigators

Abstract

Dr. Julia Kamenetzky is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the University of Arizona. She will study the molecular gas throughout galaxies that is the raw material for star formation; this gas is cold enough that atoms can bind together into molecules. This study will occur with a combination of high-resolution maps of molecular gas from the Atacama Large Millimeter Array (ALMA) to see exquisite detail in a few galaxies, and low-resolution observations of many galaxies to search for patterns in a large sample. By comparing the conditions of the gas in different types of galaxies, she will add to our understanding of which physical processes are most important for increasing and decreasing star formation. The birth and death of stars significantly impact the energetic and chemical composition of galaxies; the goal of this project is to study the raw material of star formation, molecular gas, using new technology that has only now become available to astronomers. Additionally, Dr. Kamenetzky will develop and distribute new research-based, student-focused radio astronomy curriculum with the Center for Astronomy Education (CAE). New data from Herschel indicates that higher-energy CO rotational lines (e.g. CO J=6-5) are emitted from warm molecular gas that is distinct from the well-studied cooler molecular gas traced by e.g. CO J=1-0. Dr. Kamenetzky proposes to measure the yet-unknown morphology and kinematics of this warm CO gas in high resolution with ALMA to understand its relation to well-studied galaxy components and reveal its excitation mechanisms. Additionally, new single-dish observations of low-J CO lines will be obtained using the Arizona Radio Observatory, to be combined with high-J lines from Herschel SPIRE, in order to simultaneously model the cool/warm components of gas in a large reference sample of up to 300 galaxies. Similar methods will be applied to new ALMA 3D Doppler tomography maps of recently discovered molecular CO and SiO in the remnant of Supernova 1987A. New radio astronomy curriculum will be widely distributed via the Center for Astronomy Education (CAE), a recognized provider of research-based educational materials and workshops.