On the Detection of the Methylamine, CH3NH2, in Extragalactic Sources

S. Muller, A. Beelen, M. Guélin, S. Aalto, J. H. Black, F. Combes, S. J. Curran, P. Theule, and S. N. Longmore
used the Australia Telescope Compact Array (ATCA) to study the molecular content of a foreground galaxy at z = 0.89 (FG0.89 consisting of two subsources, FG0.89SW and FG0.89NO) in absorption toward the quasar PKS 1830-211:
Molecules at z = 0.89: A 4-mm-Rest-Frame Absorption-Line Survey toward PKS 1830-211
Astron. Astrophys. 535, (2011) Art. No. A103.
Methylamine, CH3NH2, is an asymmetric top rotor displaying considerable splitting caused by the internal rotation of the CH3 group and the inversion of the NH2 group. Three transitions with K = 1 – 0 have been identified; two with J' = J" = 1 at rest frequencies of 79008 and 89956 MHz, respectively, and one with J' = J" = 2 at 78135 MHz. Even though the number of lines is a bit small, the detection can probably be viewed as secure because of the moderate line number density.

Contributor(s): H. S. P. Müller; 5, 2012