High NH2D/NH3 ratios in protostellar cores

  title={High NH2D/NH3 ratios in protostellar cores},
  author={J. Hatchell},
  journal={Astronomy and Astrophysics},
  • J. Hatchell
  • Published 2003
  • Physics
  • Astronomy and Astrophysics
Observations of low mass protostars which probe small enough size scales to be within likely CO depletion regions show the highest [NH 2 D]/[NH 3 ] ratios yet measured, of 4-33%. These molecular D/H ratios are higher than those measured on larger scales, showing that deuterium fractionation increases towards protostellar cores. As in cold clouds, such high ratios can be produced by gas-phase ion-molecule chemistry in the presence of depletion. Grain surface chemistry is less likely to explain… Expand
Searching for massive pre--stellar cores through observations of N2H+ and N2D+
Statistical modelling of NH+/ND+ + H2/HD/D2 branching ratios.
1.4-THz receiver for APEX and for GREAT on SOFIA