Detection of Interstellar Methylamine by its 2_{02}->1_{10} A_{a^{-}} State Transition

Abstract

Interstellar methylamine has been detected by its 2 H lio transition. This transition has been observed in emission in the direction of Sgr B2 and Ori A with the Parkes 64m radio telescope. A four-component multiplet has been detected in the direction of Sgr B2, but only the main (F = 3-2) line at 8777.38 MIIz has been detected in the direction of Ori A. Relative to the recently detected millimeter lines, these lines are much more intense than would be expected in thermodynamic equilibrium. We discuss the excitation temperatures of the molecular clouds and their corresponding column densities, and outline the difficulties arising in such calculations. Subject heading: molecules, interstellar