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Supernova remnants and OH (1720 MHz) masers

Published online by Cambridge University Press:  03 August 2017

Anne J. Green
Anne J. Green*
Affiliation:
School of Physics, University of Sydney, NSW 2006, Australia

Abstract

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Anomalous OH masers were detected towards supernova remnants (SNRs) more than 30 years ago. The satellite line at 1720 MHz was detected in emission, while the main lines (1665 and 1667 MHz) and the other satellite line, at 1612 MHz, occurred only in absorption. Independently, 25 years ago, a theoretical model was proposed whereby 1720 MHz OH masers could be collisionally excited by the passage of a shock through a molecular cloud. For an efficient inversion of the 1720 MHz transition, the gas should have a narrow range of physical properties, namely a kinetic temperature 50 ≤ TK ≤ 125 K, a volume density nH2 ∼ 105 cm−3, and a column density of OH gas 1016–1017 cm−2. However, it was not until 1994, with interferometric observations, that the importance of studies of these masers, formed when an SNR is in direct interaction with a molecular cloud, was realised. This discovery triggered a series of surveys to search all known Galactic SNRs. I will review the outcomes of these surveys and discuss the consequences of using 1720 MHz masers as a diagnostic tool for calculating shocked gas conditions, for magnetic field determinations (from Zeeman splitting measurements) and for measuring the properties of SNRs.

Type
Part 1. Star Formation
Information
Symposium - International Astronomical Union , Volume 206: Cosmic Masers: From Protostars to Blackholes , 2002 , pp. 204 - 211
Copyright
Copyright © Astronomical Society of the Pacific 2002 

References

Arikawa, Y., Tatematsu, K., Sekimoto, Y. & Takehashi, T. 1999, PASJ, 51, L7 CrossRefGoogle Scholar
Brogan, C. L., Frail, D. A., Goss, W. M., & Troland, T. H. 2000, ApJ, 537, 875 CrossRefGoogle Scholar
Claussen, M. J., Goss, W. M. & Frail, D. A. 1999a, AJ, 117, 1387 CrossRefGoogle Scholar
Claussen, M. J., Frail, D. A., Goss, W. M., & Desai, K. 1999b, ApJ, 522, 349 CrossRefGoogle Scholar
Cohen, R. J. 1989, Rep Prog Phys, 52, 881 CrossRefGoogle Scholar
De Noyer, L. K. 1979, ApJ, 232, L165 CrossRefGoogle Scholar
Dubner, G. M., Green, A. J., Goss, W. M., Bock, D. C.-J. & Giacani, E. B. 1998, AJ, 116, 1842 CrossRefGoogle Scholar
Elitzur, M. 1976, ApJ, 203, 124 CrossRefGoogle Scholar
Elitzur, M., Hollenbach, D. J., & McKee, C. F. 1989, ApJ, 346, 983 CrossRefGoogle Scholar
Frail, D. A. & Mitchell, G. F. 1998, ApJ, 508, 690 CrossRefGoogle Scholar
Frail, D. A., Goss, W. M., & Slysh, V. I. 1994, ApJ, 424, L111 Google Scholar
Frail, D. A., Goss, W. M., Reynoso, E. M., Giacini, E. B., Green, A. J., & Otrupcek, R. 1996, AJ, 111, 1651 CrossRefGoogle Scholar
Goss, W. M., & Robinson, B. J. 1968, Astrophys. Lett., 2, 81 Google Scholar
Green, A. J., Frail, D. A., Goss, W. M. & Otrupcek, R. 1997, AJ, 114, 2058 CrossRefGoogle Scholar
Green, D. A. 1996, A Catalogue of Galactic Supernova Remnants (1996 August version), Milliard Radio Astronomy Observatory, Cambridge, U.K. (available on the Web at “http://www.mrao.cam.ac.uk/surveys/snrs/”)Google Scholar
Hollenbach, D. J. 1997, in IAU Symp. 182, Herbig-Haro Flows and the Birth of Low Mass Stars, eds. Reipurth, B. & Bertout, C., 181 CrossRefGoogle Scholar
Hollenbach, D. J. & McKee, C. F. 1989, ApJ, 342, 306 CrossRefGoogle Scholar
Koralesky, B., Frail, D. A., Goss, W. M., Claussen, M. J. & Green, A. J. 1998, AJ, 116, 1323 Google Scholar
Lockett, P. & Elitzur, M. 1989, ApJ, 344, 525 CrossRefGoogle Scholar
Lockett, P., Gauthier, E. & Elitzur, M. 1999, ApJ, 511, 235 CrossRefGoogle Scholar
Neufeld, D. A. & Delgarno, A. 1989, ApJ, 340, 869 CrossRefGoogle Scholar
Reach, W. T. & Rho, J. 1998, ApJ, 507, L93 CrossRefGoogle Scholar
Reid, M. J. & Moran, J. M. 1988, Galactic & Extragalactic Radio Astronomy, eds. Verschuur, G. L. & Kellermann, K. I. (New York: Springer), 255 CrossRefGoogle Scholar
Turner, B. E. 1969, ApJ, 157, 103 CrossRefGoogle Scholar
van Dishoeck, E. F., Jansen, D. J., & Phillips, T. G. 1993, A&A, 279, 541 Google Scholar
Wardle, M. 1999, ApJ, 527, L109 CrossRefGoogle Scholar
Weinreb, S., Barrett, A. H., Meeks, M. L. & Henry, J. C. 1963, Nature, 200, 829 Google Scholar
Wootten, A. 1977, ApJ, 216, 440 CrossRefGoogle Scholar
Wootten, A. 1981, ApJ, 245, 105 Google Scholar
Yusef-Zadeh, F., Uchida, K. I. & Roberts, D. 1995, Science, 270, 1801 CrossRefGoogle Scholar
Yusef-Zadeh, F., Roberts, D. A., Goss, W. M., Frail, D. A., & Green, A. J. 1996, ApJ, 466, L25 CrossRefGoogle Scholar
Yusef-Zadeh, F., Goss, W. M., Roberts, D. A., Robinson, B. & Frail, D. A. 1999, ApJ, 527, 172 CrossRefGoogle Scholar