| 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. |
