Local constraints on alcohol--thioalcohol analogs in G35.2N — E8 Intelligence Research

The chemistry of sulfur-bearing complex organic molecules in dense star-forming environments remains uncertain, partly because the dominant sulfur reservoirs in dense gas and ices are poorly identified. Alcohol--thioalcohol pairs allow direct comparisons of structurally related O- and S-bearing molecules. We present ALMA Band 6 observations of CH$_3$OH/CH$_3$SH and C$_2$H$_5$OH/C$_2$H$_5$SH toward three spectral-extraction positions (MM3-pos, MM4-pos, and MM5-pos) in the MM3--MM5 region of G35.2N. Local thermodynamic equilibrium modeling yields column densities and abundance ratios. CH$_3$OH column densities were inferred from $^{13}$CH$_3$OH assuming $^{12}$C/$^{13}$C = 50 to mitigate optical-depth effects. CH$_3$OH, CH$_3$SH, and C$_2$H$_5$OH are robustly constrained at all three positions; C$_2$H$_5$SH is robustly constrained at MM3-pos and MM5-pos but remains tentative at MM4-pos. The corresponding adopted column-density ranges are $(1.8-2.7)\times10^{18}$, $(1.7-2.6)\times10^{16}$ Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com