Abstract
Recent observations show that the OH 1720 MHz maser is a powerful probe of the shocked region where a supernova remnant strikes a molecular cloud. We perform a thorough study of the pumping of this maser and find tight constraints on the physical conditions needed for its production. The presence of the maser implies moderate temperatures (50-125 K) and densities (~105 cm-3) and OH column densities of order 1016 cm-2. We show that these conditions can exist only if the shocks are of C-type. J-shocks fail by such a wide margin that the presence of this maser could become the most powerful indicator of C-shocks. These conditions also mean that the 1720 MHz maser will be inherently weak compared with the other ground-state OH masers. All the model predictions are in good agreement with the observations.
Document Type
Article
Publication Date
1-20-1999
Digital Object Identifier (DOI)
http://dx.doi.org/10.1086/306667
Repository Citation
Lockett, Phil; Gauthier, Eric; and Elitzur, Moshe, "OH 1720 Megahertz Masers in Supernova Remnants: C-Shock Indicators" (1999). Physics and Astronomy Faculty Publications. 219.
https://uknowledge.uky.edu/physastron_facpub/219
Notes/Citation Information
Published in The Astrophysical Journal, v. 511, no. 1, p. 235-241.
© 1999. The American Astronomical Society. All rights reserved.
The copyright holder has granted permission for posting the article here.