Physics Commons^™

Excited-State Oh Masers And Supernova Remnants, Ylva M. Pihlström, Vincent L. Fish, Loránt O. Sjouwerman, Laura K. Zschaechner, Philip B. Lockett, Moshe Elitzur

Physics and Astronomy Faculty Publications

The collisionally pumped, ground-state 1720 MHz maser line of OH is widely recognized as a tracer for shocked regions and observed in star-forming regions and supernova remnants. Whereas some lines of excited states of OH have been detected and studied in star-forming regions, the subject of excited-state OH in supernova remnants-where high collision rates are to be expected-is only recently being addressed. Modeling of collisional excitation of OH demonstrates that 1720, 4765, and 6049 MHz masers can occur under similar conditions in regions of shocked gas. In particular, the 6049 and 4765 MHz masers become more significant at increased OH …