Detection of extragalactic CF+ toward PKS1830-211 -- Chemical   differentiation in the absorbing gas
  We report the first extragalactic detection of CF+, the fluoromethylidynium ion, in the z=0.89 absorber toward PKS1830-211. We estimate an abundance of ~3E-10 relative to H2 and that ~1% of fluorine is captured in CF+. The absorption line profile of CF+ is found to be markedly different from that of other species observed within the same tuning, and is notably anti-correlated with CH3OH. On the other hand, the CF+ profile resembles that of [C I]. Our results are consistent with expected fluorine chemistry and point to chemical differentiation in the column of absorbing gas. 
S. Muller (Department of Earth and Space Sciences, Chalmers University   of Technology, Onsala Space Observatory, SE-43992 O...
astro-ph.GA