Terahertz spectroscopy of the15NH2amidogen radical

L. Margulès, M. A. Martin-Drumel, O. Pirali, S. Bailleux, G. Wlodarczak, P. Roy, E. Roueff, M. Gerin
2016 Astronomy and Astrophysics  
Context. The determination of isotopic ratios in interstellar molecules is a powerful probe of chemical routes leading to their formation. In particular, the 14 N/ 15 N abundance ratio of nitrogen-bearing species provides information on possible fractionation mechanisms. Up to now there is no accurate determination of this ratio in the interstellar medium (ISM) for the amidogen radical, NH 2 . Aims. This work is aimed at determining rotational frequencies of 15 NH 2 to enable its astronomical
more » ... its astronomical detection, which will help to understand the formation mechanisms of nitrogen hydrides in the ISM. Methods. We performed complementary measurements using both synchrotron-based, broadband far-infrared and high-resolution, submillimeter-wave frequencies to investigate the pure rotational spectrum of the 15 NH 2 species. Results. The first spectroscopic study of the 15 N-isotopologue of the amidogen radical yielded an accurate set of molecular parameters. Conclusions. Accurate frequencies are now available for 15 NH 2 up to 7 THz (with N ≤ 13) allowing dedicated astronomical searches to be undertaken.
doi:10.1051/0004-6361/201628201 fatcat:gw5egd7hwnhgjlrz6msqq6joey