Carbon isotopic fractionation in molecular clouds

  title={Carbon isotopic fractionation in molecular clouds},
  author={L. Colzi and O. Sipil{\"a} and E. Roueff and P. Caselli and F. Fontani},
  journal={arXiv: Astrophysics of Galaxies},
C-fractionation has been studied from a theoretical point of view with different models of time-dependent chemistry, including both isotope-selective photodissociation and low-temperature isotopic exchange reactions. Recent chemical models predict that the latter may lead to a depletion of $^{13}$C in nitrile-bearing species, with $^{12}$C/$^{13}$C ratios two times higher than the elemental abundance ratio of 68 in the local ISM. Since the carbon isotopic ratio is commonly used to evaluate the… Expand
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Secondly, in Sect. A.2 we compare our results to the 12C/13C ratios predicted by Furuya et al
  • Appendix A.1: Comparison with Roueff et al
  • 2015
Carbon isotopic fractionation in molecular clouds Fig. A.1: Abundances (left panel) and 12C/13C ratios (right panel) from our chemical model using a density of 105 cm and temperature of 10 K
  • (same as Furuya et al
  • 2011
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