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NRAO/Socorro Colloquium Series

Todd Thompson

Ohio State

Feedback Processes in Rapidly Star-Forming Galaxies 


I will describe a set of projects aimed at developing a physical picture of the feedback and regulation processes in the ISM of rapidly star-forming and ultra-luminous infrared galaxies. The UV radiation produced by massive stars in the ISM of starbursts is absorbed, scattered, and reprocessed into the IR by dust grains. I will argue that the associated radiation pressure may provide the dominant vertical support against gravity. I will discuss the implications of this important feedback process at the galaxy scale, and at the scale of individual star clusters. Because the system radiates at its Eddington limit (for dust), starbursts supported by radiation pressure achieve a characteristic radiative flux and their ``Schmidt Law'' for star formation changes qualitatively with respect to normal star-forming galaxies.  I will also describe observational and theoretical constraints on the magnetic field strength and cosmic ray energy density in starbursts, with direct implications for the origin of the FIR-Radio correlation, the shape of the radio spectra of starbursts, and their observability at GeV energies by Fermi.




September 28, 2012
11:00 am

Array Operations Center Auditorium

All NRAO employees are invited to attend via video, available in Charlottesville Room 230, Green Bank Room 137 and Tucson N525.

Local Host: Minnie Mao

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