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.
The cyanomethyl radical shows at low quantum numbers complicated pattern caused by fine structure (FS) and hyperfine structure (HFS) of the N nucleus; at even Ka, HFS of the two equivalent H nuclei occurs. Two Ka = 0 transitions with J" = 2 and 3 were detected. The lines were broadened because of FS and HFS.