Haystack Observations of CS and CH3OH Toward Star Forming Regions

Abstract

We report ¹²CS J= 1 → 0 observations toward 20 star forming regions conducted with the MIT 37m Haystack telescope. Three of the sources were also observed in the ¹³CS J= 1 → 0 line, and five sources where observed in the CH₃OH JK = 70 → 6¹ A+ transition at 44 GHz. We detected ¹³CS and CH₃OH emission toward all sources observed, and ¹²CS emission toward 19 of the 20 sources in the sample, 11 of which are new detections. We found a strong correlation between the ¹²CS FWHM and the source distance, indicating the potential use of ¹²CS J= 1 → 0 emission as a tool to estimate distances to star forming regions. We also report detection of CH₃OH 44 GHz maser variability in most of the observed sources.