The Complete, Temperature Resolved Spectrum Of Methanol Between 214 And 265 Ghz

We have studied methanol, one of the so-called ‘astronomical weeds’, in the 215--265 GHz band. We have gathered a set of intensity calibrated, complete, experimental, and temperature resolved spectra from across the temperature range of 240--389 K. A number of low lying transitions, including the $\nu_t = 3$ , have not been produced by available catalogs. Using our previously reported method of analysis\footnote{S. Fortman et al. 2014 ApJ 782 75} we were able generate a line list that contains lower state energies and linestrengths, for all of the observed lines in the band. This line list includes those lines which have no quantum mechanical assignment. In addition to this line list we provide a point by point method capable of generating the complete spectrum at an arbitrary temperature. The sensitivity of the point by point analysis is such that we are able to identify lines which would not have manifest in a single scan across the band. The consequence has been to reveal not only a number of new methanol lines, but also trace amounts of contaminants. We show how the intensities from the contaminants can be removed with indiscernible impact on the signal from methanol. To do this we use the point by point results from our previous studies of these contaminants. The efficacy of this process serves as strong proof of concept for usage of our point by point results on the problem of the weeds. The success of this approach for dealing with the weeds has also previously been reported\footnote{S.~Fortman et al. 2012 J.~Mol.~Spectrosc. 782, 75}