Scott J. Kenyon: Galaxy Formation

In 1978, Larson & Tinsley first recognized that star formation triggered by galaxy-galaxy interactions is a basic ingradient of galaxy formation and evolution. Numerous observational studies at low and high redshift support and refine these initial results.

In the 1990's, Mihos and Hernquist developed a theoretical picture of star formation triggered by gravitational interactions among close pairs of galaxies. During a close pass, tides drive molecular gas to the centers of each galaxy and trigger a burst of star formation. As the galaxies move apart, the burst continues and declines in intensity.

I work with Betsy Barton and Margaret Geller on tests of this picture. Using data from the CfA Redshift Survey, we were the first to show that several indicators of star formation are inversely correlated with the projected separation of the pair (as expected: closer pairs should have more star formation). You can read about these results here. In two other papers, we used optical data and infrared data to constrain burst properties and to compare these close pairs with ultraluminous infrared galaxies.


Infrared and ultraviolet images probe triggered star formation in interacting pairs of galaxies.
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