SIMBAD references

2018MNRAS.476.4994F - Mon. Not. R. Astron. Soc., 476, 4994-5005 (2018/June-1)

Tracing the atomic nitrogen abundance in star-forming regions with ammonia deuteration.


Abstract (from CDS):

Partitioning of elemental nitrogen in star-forming regions is not well constrained. Most nitrogen is expected to be partitioned among atomic nitrogen (N I), molecular nitrogen ( N2), and icy N-bearing molecules, such as NH3 and N2. N I is not directly observable in the cold gas. In this paper, we propose an indirect way to constrain the amount of N I in the cold gas of star-forming clouds, via deuteration in ammonia ice, the [ND2H/NH2D]/[NH2D/NH3] ratio. Using gas-ice astrochemical simulations, we show that if atomic nitrogen remains as the primary reservoir of nitrogen during cold ice formation stages, the [ND2H/NH2D]/[NH2D/NH3] ratio is close to the statistical value of 1/3 and lower than unity, whereas if atomic nitrogen is largely converted into N-bearing molecules, the ratio should be larger than unity. Observability of ammonia isotopologues in the inner hot regions around low-mass protostars, where ammonia ice has sublimated, is also discussed. We conclude that the [ND2H/NH2D]/[NH2D/NH3] ratio can be quantified using a combination of Very Large Array and Atacama Large Millimeter/submillimeter Array observations with reasonable integration times, at least towardsIRAS 16293-2422, where high molecular column densities are expected.

Abstract Copyright: © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): astrochemistry - stars: formation - ISM: clouds - ISM: molecules

Simbad objects: 8

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2018MNRAS.476.4994F and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact