Nitrogen hydrides in interstellar gas Herschel/HIFI observations towards G10.6-0.4 (W31C)
Artikel i vetenskaplig tidskrift, 2010

The HIFI instrument on board the Herschel Space Observatory has been used to observe interstellar nitrogen hydrides along the sight-line towards G10.6-0.4 in order to improve our understanding of the interstellar chemistry of nitrogen. We report observations of absorption in NH N = 1 <- 0, J = 2 <- 1 and ortho-NH2 1(1,1) <- 0(0,0). We also observed ortho-NH3 1(0) <- 0(0) and 2(0) <- 1(0), para-NH3 2(1) <- 1(1), and searched unsuccessfully for NH+. All detections show emission and absorption associated directly with the hot-core source itself as well as absorption by foreground material over a wide range of velocities. All spectra show similar, non-saturated, absorption features, which we attribute to diffuse molecular gas. Total column densities over the velocity range 11-54 km s(-1) are estimated. The similar profiles suggest fairly uniform abundances relative to hydrogen, approximately 6 x 10(-9), 3 x 10(-9), and 3 x 10(-9) for NH, NH2, and NH3, respectively. These abundances are discussed with reference to models of gas-phase and surface chemistry.


molecular processes

line: formation



ISM: molecules



submillimetre: ISM






ISM: abundances

molecular absorption


Carina Persson

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

John H Black

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

J. Cernicharo

J. R. Goicoechea

G.E. Hassel

E. Herbst

M. Gerin

M. de Luca

T. A. Bell

A. Coutens

E. Falgarone

P. F. Goldsmith

H. Gupta

M. Kazmierczak

D. C. Lis

B. Mookerjea

D. A. Neufeld

J. C. Pearson

T. G. Phillips

P. Sonnentrucker

J. Stutzki

C. Vastel

S. Yu

F. Boulanger

E. Dartois

P. Encrenaz

T. R. Geballe

T. Giesen

B. Godard

C. Gry

P. Hennebelle

P. Hily-Blant

C. Joblin

R. Kolos

J. Krelowski

J. Martin-Pintado

K. Menten

Raquel Rodriguez-Monje

M. Perault

R. Plume

M. Salez

S. Schlemmer

M. Schmidt

D. Teyssier

I. Peron

P. Cais

P. Gaufre

A. Cros

L. Ravera

Pasadena C. A. Anal

Large Atacama

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 521 Article Number: L45 - L45


Astronomi, astrofysik och kosmologi