## Files in this item

FilesDescriptionFormat

application/pdf

497652.pdf (1MB)
PresentationPDF

application/pdf

1356.pdf (22kB)
AbstractPDF

## Description

 Title: CLASS I METHANOL MASER CONDITIONS NEAR SNRS Author(s): McEwen, Bridget C. Contributor(s): Sjouwerman, Lorﾇnt O.; Pihlstrﾚm, Ylva M. Subject(s): Astronomy Abstract: We present results from calculations of the physical conditions necessary for the occurrence of 36.169 ($4_{-1}-3_{0}, E$), 44.070 ($7_{0}-6_{1},A^+$), 84.521 ($5_{-1}-4_{0},E$), and 95.169 ($8_{0}-7_{1},A^+$) GHz methanol (CH$_3$OH) maser emission lines near supernova remnants (SNRs), using the MOLPOP-CEP program. The calculations show that given a sufficient methanol abundance, methanol maser emission arises over a wide range of densities and temperatures, with optimal conditions at $nsim 10^4-10^6$ cm$^{-3}$ and $T>60$ K. The 36~GHz and 44~GHz transitions display more significant maser optical depths compared to the 84~GHz and 95~GHz transitions over the majority of physical conditions. It is also shown that line ratios are an important and applicable probe of the gas conditions. The line ratio changes are largely a result of the $E$-type transitions becoming quenched faster at increasing densities. The modeling results will be discussed using recent observations of CH$_3$OH masers near the SNRs G1.4$-$0.1, W28, and Sgr,A,East and used as a diagnostic tool to estimate densities and temperatures of the regions in which the CH$_3$OH masers are observed. Issue Date: 25-Jun-15 Publisher: International Symposium on Molecular Spectroscopy Citation Info: ACS Genre: CONFERENCE PAPER/PRESENTATION Type: Text Language: English URI: http://hdl.handle.net/2142/79419 Date Available in IDEALS: 2016-01-05
﻿