Description |
By using new laboratory transition frequencies of the H _2 F ^+ ion, we propose a search for the ion in interstellar space. The detection will contribute to understanding the fluorine chemistry through determined abundances of fluorine bearing molecules.
The precursor of H2F+, the HF molecule detected in diffuse molecular cloud towards W49N has a fairly large abundance of (5.5-6.9) \times 10^{13} cm ^{-2} Since the dipole moment of H _2 F ^+ 2.79 D is large compared with 1.89 D of H _2 Cl ^+ , the H _2 F ^+ ion may be detectable in such diffuse molecular clouds where H _3^+ is abundant.
By considering various things, we propose searches for H _2 F ^+ toward three types of sources, (1) G10.6-0.4(W31C), where HF has been detected, (2) NGC 6334I, where H _2 Cl ^+ has been detected, (3) galactic central region sources : GC IRS 21 and 2Mass J1747, where H _3^+ is known to be abundant. For NGC 6334I and galactic sources, HF observations are also proposed, because of no reports for HF. |