Hostname: page-component-84b7d79bbc-g78kv Total loading time: 0 Render date: 2024-07-28T13:17:15.483Z Has data issue: false hasContentIssue false
  • English
  • Français

Searching for new OH megamasers out to redshifts z>1

Published online by Cambridge University Press:  24 July 2012

Kyle W. Willett
Kyle W. Willett*
Affiliation:
Center for Astrophysics and Space Astronomy, University of ColoradoUCB 391, Boulder, CO 80304, United States School of Physics and Astronomy, University of Minnesota116 Church St. SE, Minneapolis, MN 55455, United States email: willett@physics.umn.edu
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We have carried out a search for 18-cm OH megamaser (OHM) emission with the Green Bank Telescope. The targeted galaxies comprise a sample of 121 ULIRGs at 0.09<z<1.5, making this is the first large, systematic search for OHMs at z>0.25. Nine new detections of OHMs are reported, all at redshifts z<0.25. For the remainder of the galaxies, observations constrain the upper limit on OH emission; this rules out OHMs of moderate brightness (LOH>103 L⊙) for 26% of the sample, and extremely bright OHM emission (LOH>104 L⊙) for 73% of the sample. Losses from RFI result in the OHM detection fraction being significantly lower than expected for galaxies with LIR>1012 L⊙. The new OHM detections are used to calculate an updated OH luminosity function, with Φ∝ LOH−0.66; this slope is in agreement with previous results. Non-detections of OHMs in the COSMOS field constrain the predicted sky density of OHMs; the results are consistent with a galaxy merger rate evolving as (1+z)m, where m≤6.

Keywords

masersradio lines: galaxiesinfrared: galaxiesgalaxies: interactions
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 8 , Symposium S287: Cosmic Masers - from OH to H0 , January 2012 , pp. 345 - 349
Copyright
Copyright © International Astronomical Union 2012

References

Bridge, C. R., Carlberg, R. G., & Sullivan, M. 2010, ApJ, 709, 1067CrossRefGoogle Scholar
Briggs, F. H. 1998, A&A, 336, 815Google Scholar
Darling, J. & Giovanelli, R. 2000, AJ, 119, 3003CrossRefGoogle Scholar
Darling, J. & Giovanelli, R. 2001, AJ, 121, 1278CrossRefGoogle Scholar
Darling, J. & Giovanelli, R. 2002a, AJ, 124, 100CrossRefGoogle Scholar
Darling, J. & Giovanelli, R. 2002b, ApJ, 572, 810CrossRefGoogle Scholar
Goto, T. et al. 2011, MNRAS, 410, 573CrossRefGoogle Scholar
Kartaltepe, J. et al. 2010, ApJ, 709, 572CrossRefGoogle Scholar
Kim, D. & Sanders, D. B. 1998, ApJS, 119, 41CrossRefGoogle Scholar
Stanford, S. A., Stern, D., van Breugel, W., & De Breuck, C. 2000, ApJS, 131, 185CrossRefGoogle Scholar
Willett, K. W., Darling, J., Spoon, H. W. W., Charmandaris, V., & Armus, L. 2011, ApJ, 730, 56CrossRefGoogle Scholar