Observations of the methanol 4−1−30 E line in molecular clouds

摘要: Abstract Searches for new sources and regular monitoring of several molecular clouds in the methanol 44−1−30 E transition are progress since 1988 with 22 meter radio telescope Lebedev Physical Institute. Spectra several-point maps (when available) presented briefly discussed. Several emit both “broad” (a few km/s) “spike” (≤1 spectral features. No time variations were detected within accuracy observations. The common procedure column density calculations 4−1−30 features is critically analyzed. It shown that treating these as optically thin “thermal” may lead to an over estimation by order magnitude. astrophysical nature components