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On the Feasibility of Disk Chemical Modeling

Dmitry Semenov·Yaroslav Pavluchenkov·Thomas Henning·Eric Herbst·Ewine van Dishoeck
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Abstract

In this paper, we compare the results of the modeling of a protoplanetary disk chemical evolution obtained with the UMIST95 and ``New Standard Model'' (NSM) chemical databases. Assuming the same initial conditions, it is found that the substitution of one chemical network by another causes almost no difference for the disk ionization degree. In contrast, the NSM and UMIST95 abundances of CO can differ by a factor of a hundred at some regions of the disk surface. However, relevant CO vertical column densities differ much less, at most by a factor of a few. In addition, we synthesize the single-dish CO(J=3-2) line by means of the 2D line radiative transfer for both considered chemical networks. It is shown that the intensity of this line in the case of the UMIST95 abundances is lower compared to the NSM case by about 15%.

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Dmitry Semenov, Yaroslav Pavluchenkov, Thomas Henning, Eric Herbst, Ewine van Dishoeck. 2003-11-20. On the Feasibility of Disk Chemical Modeling. https://arxiv.org/abs/astro-ph/0311469

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