The distribution of ND 2 H in LDN 1689N

  title={The distribution of ND 2 H in LDN 1689N},
  author={Maryvonne Gerin and D. C. Lis and Sabine D. Philipp and Rolf Gusten and {\`E}velyne Roueff and Vincent R{\'e}v{\'e}ret},
  journal={Astronomy and Astrophysics},
Aims. Finding tracers of the innermost regions of prestellar core s is important for understanding their chemical and dynamical evolution before the onset of gravitational collapse. While classical molec ular tracers, such as CO and CS, have been shown to be strongly depleted in cold, dense gas by condensation on grain mantles, it has been a subject of discussion to what extent nitrogen-bearing species, such as ammonia, are affected by this process. As deuterium fractionation is effi cient in… 

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