Molecular abundance ratios as a tracer of accelerated collapse in regions of high mass star formation?

Lintott, C. J.; Viti, S.; Rawlings, J. M. C.; Williams, D. A.; Hartquist, T. W.; Caselli, P.; Zinchenko, I.; Myers, P.

Molecular abundance ratios as a tracer of accelerated collapse in regions of high mass star formation?

Authors

Description

Recent observations suggest that the behaviour of tracer species such as N_2H+ and CS is significantly different in regions of high and low mass star formation. In the latter, N_2H+ is a good tracer of mass, while CS is not. Observations show the reverse to be true in high-mass star formation regions. We use a computational chemical model to show that the abundances of these and other species may be significantly altered by a period of accelerated collapse in high mass star forming regions. We suggest these results provide a potential explanation of the observations, and make predictions for the behaviour of other species.
5 pages, 3 figures To be published in the Astrophysical Journal