---
author:
- 'M. Melosso'
- 'L. Bizzocchi'
- 'O. Sipilä'
- 'B. M. Giuliano'
- 'L. Dore'
- 'F. Tamassia'
- 'M.-A. Martin-Drumel'
- 'O. Pirali'
- 'E. Redaelli'
- 'P. Caselli'
bibliography:
- 'nhd\_iras16293.bib'
date: 'Received ; accepted –'
subtitle: 'Amidogen deuteration in IRAS 16293–2422'
title: First detection of and in the interstellar medium
---

[Deuterium fractionation processes in the interstellar medium (ISM) have been shown to be highly efficient in the family of nitrogen hydrides. To date, observations were limited to ammonia (, , ) and imidogen radical () isotopologues.]{} [We want to explore the high frequency windows offered by the *Herschel Space Observatory* to search for deuterated forms of amidogen radical and to compare the observations against the predictions of our comprehensive gas-grain chemical model.]{} [Making use of the new molecular spectroscopy data recently obtained at high frequencies for and , both isotopologues have been searched for in the spectral survey towards the class 0 IRAS 16293-2422, a source in which , and their deuterated variants have been previously detected. We used the observations carried out with HIFI (Heterodyne Instrument for the Far Infrared) in the framework of the key program “Chemical *Herschel* surveys of star 