On the Detection of Propadienylidene, l-C3H2, 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.
Propadienylidene, l-C3H2, was identified by three Ka = 1 ortho transitions (2 with J" = 2 and the lower J" = 3) and one with Ka = 0 (para) and J" = 3. The OPR is compatible with the high temperature limit of 3. The abundance ratio c-C3H2 to l-C3H2 is about 25, between 3–5 in diffuse clouds, and 70 found in the dark cloud TMC-1.

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