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

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

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.

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C. J. Lintott, S. Viti, J. M. C. Rawlings, D. A. Williams, T. W. Hartquist, P. Caselli, I. Zinchenko, P. Myers. 2004-10-27. Molecular abundance ratios as a tracer of accelerated collapse in regions of high mass star formation?. https://doi.org/10.1086/427164

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