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The Arecibo OH Megamaser Survey and the Galaxy Merger Rate

Jeremy Darling·Riccardo Giovanelli
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Abstract

We present the current results of a survey for OH megamasers (OHMs) underway at the Arecibo Observatory. The survey is 2/3 complete and has produced a high OHM detection rate (1 in 6) from a redshift-selected sample of IRAS galaxies. The survey will relate the OHM luminosity function to the galaxy merger rate, allowing subsequent blind OHM surveys to measure the galaxy merger rate as a function of cosmic time. The survey has also made the first detection of strong variability in OHMs. Variability will provide a powerful tool for understanding the small-scale physical settings and mechanisms of OHMs.

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Jeremy Darling, Riccardo Giovanelli. 2000-09-13. The Arecibo OH Megamaser Survey and the Galaxy Merger Rate. https://arxiv.org/abs/astro-ph/0009205

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