2002/05/13 by Jeremy Darling, Riccardo Giovanelli · 4 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1086/341166
28 pages, 14 figures, accepted by AJ. (AASTeX, includes emulateapj5 and onecolfloat5)
arxiv created 2002/05/13 · openalex publication_date 2002/07/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present the final results from the Arecibo ObservatoryThe Arecibo Observatory is part of the National Astronomy and Ionosphere Center, which is operated by Cornell University under a cooperative agreement with the National Science Foundation. OH megamaser survey. We discuss in detail the properties of the remaining 18 OH megamasers detected in the survey, including three redetections. We place upper limits on the OH emission from 85 nondetections and examine the properties of 25 ambiguous cases for which the presence or absence of OH emission could not be determined. The complete survey has discovered 50 new OH megamasers (OHMs) in (ultra)luminous infrared galaxies ([U]LIRGs), which doubles the sample of known OHMs and increases the sample at z > 0.1 sevenfold. The Arecibo OH megamaser survey indicates that the OHM fraction in LIRGs is an increasing function of the far-IR luminosity ( L FIR ) and far-IR color, reaching a fraction of roughly in the warmest ULIRGs. Significant relationships between OHMs and their hosts are few, primarily because of a mismatch in size scales of measured properties and an intrinsic scatter in OHM properties roughly equal to the span of the data set. We investigate relationships between OHMs and their hosts with a variety of statistical tools including survival analysis, partial correlation coefficients, and a principal component analysis. There is no apparent OH megamaser "fundamental plane." We compile data on all previously known OHMs and evaluate the possible mechanisms and relationships responsible for OHM production in merging systems. The OH-FIR relationship is reexamined by using the doubled OHM sample and found to be significantly flatter than previously thought: L OH ∝ L . This nearly linear dependence suggests a mixture of saturated and unsaturated masers, either within individual galaxies or across the sample.