C.D.S. - SIMBAD4 rel 1.7 - 2019.12.15CET19:31:05

2007A&A...464..245R - Astronomy and Astrophysics, volume 464, 245-252 (2007/3-2)

Deuterium fractionation in warm dense interstellar clumps.


Abstract (from CDS):

In a recently published 1-millimeter line survey of the Orion Bar by Leurini et al., the confirmation of dense neutral clumps was reported based mainly on an analysis of methanol spectral lines. Within these clumps, a high abundance ratio was found between the deuterated isotopologue DCN and HCN. In this paper, we use steady-state chemical modelling to determine if the DCN/HCN abundance ratio can be understood in terms of gas-phase processes. Our results show that, at temperatures (50-75K) and densities (5-20x106cm–3) in the vicinity of those measured, the calculated DCN/HCN abundance ratio can reach 0.01 or even higher, in good agreement with the measured range of 0.007-0.009. Moreover, the fractional abundance of HCN is also calculated to be in the vicinity of that reported. Other computed abundance ratios between deuterated and normal isotopologues are reported for the physical conditions of the clumps. The abundance ratios are analyzed as functions of temperature and density in terms of a simple formula. In general, calculated ratios can be somewhat dependent on the choice of two very different sets of elemental abundances, one of which is the ``standard'' low-metal set, while the other we term the ``warm-core'' set.

Abstract Copyright:

Journal keyword(s): ISM: abundances - ISM: molecules - molecular processes

Simbad objects: 2

goto Full paper

goto View the reference in ADS

Number of rows : 2

N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
1 NAME Orion Bright Bar reg 05 35 22.30 -05 24 33.0           ~ 693 0
2 LDN 183 MoC 15 54 12.2 -02 49 42           ~ 674 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2007A&A...464..245R and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact