PI: Elizabeth J. Barton, Dominion Astrophysical Observatory, Betsy.Barton@hia.nrc.ca
Address: 5071 West Saanich Rd., Victoria, British Columbia V9E 2E7, Canada
CoI: Scott J. Kenyon, Smithsonian Astrophysical Observatory
CoI: Margaret J. Geller, Smithsonian Astrophysical Observatory
Title: Stellar Populations and Dust in Galaxies in Close Pairs: Measuring the Impact of Interactions
Abstract: Galaxy-galaxy interactions are a driver of galaxy evolution, although their total contribution from high redshift to the present epoch remains unknown. To quantify the impact of interactions at the current epoch and to measure the selection effects relevant to pair counts at high redshift, we propose to continue a project to image, in U, V, J, H, and K, a sample of 84 low-redshift galaxy pairs and n-tuples with evidence for recent (\lesssim 10^7-year-old) star formation. Because of poor weather during previous runs, only 14 systems have completed observations. We are currently proposing to complete the Fall sample of 45 systems, all of which require some observations. With the images, we plan to measure the relative abundances of the old (several Gyr) and young (\lesssim 1 Gyr) stellar populations and to constrain the amount of dust. The observations are part of a larger study of a complete, statistical sample of galaxies in pairs and n- tuples selected from the CfA2 redshift survey. The goals of the study are to measure the durations, initial (stellar) mass functions, and total luminosities of tidally-triggered bursts of star formation - and to use these data to provide a foundation for measuring the merger rate as a function of cosmic epoch.
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