The C3H2 2(20)-2(11) transition: absorption in cold dark clouds

Astrophys J. 1986 Aug 15;307(2):L69-73. doi: 10.1086/184730.

Abstract

The first observations of the 2(20)-2(11) transition of cyclopropenylidene (C3H2) at 21.6 GHz are described. In all cases where it has been detected, the line appears in absorption, showing that this transition is "refrigerated" (i.e., Tex < 2.7 K) in cold dust clouds. These results are compared with those for the 1(10)-1(01) transition of C3H2, and the consequences for the excitation of C3H2 qualitatively discussed.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Astronomical Phenomena
  • Astronomy*
  • Cosmic Dust
  • Extraterrestrial Environment*
  • Hydrocarbons, Cyclic / analysis*
  • Microwaves
  • Temperature

Substances

  • Cosmic Dust
  • Hydrocarbons, Cyclic