Time dependent chemistry in Planck cold clouds?
Abstract
We present a set of time dependent chemical evolution models based on the 2012 edition of the UMIST Database for Astrochemistry (McElroy et al. 2013) for a wide range of initial physical cloud parameters (10K<T<20K, 1000cm-3<n(H2)<100000cm-3, 1<AV<10 and with various values for the external ultraviolet radiation field). Our computation model applies the full UMIST gas-phase reaction network which contain the whole set of 6173 reactions among 467 species. The input physical conditions were used as observed in a sample of selected Planck cold clouds (Juvela et al. 2012). The UMIST model predicts significant time dependent variations of the relative abundances of CO, CH, OH, HCO+, HCN, HNC, NH3, N2H+ and H2CO molecules. We compared our detailed chemical model results with the observed ratios. Is that an indication of age differences? The question is discussed in our poster.
- Publication:
-
IAU General Assembly
- Pub Date:
- August 2015
- Bibcode:
- 2015IAUGA..2253148B