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arXiv · 2008.10377

The role of FUV Pumping in exciting the [Oi] lines in Protostellar Disks and Winds

Ahmad Nemer·Jeremy Goodman·Lile Wang
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Abstract

We use Cloudy to re-examine excitation of [Oi] 6300 A and [Oi] 5577 A in the X-ray driven photo-evaporative wind models of Owen and collaborators, and in more recent magnetothermal models by Wang et al. We find that, at the measured accretion luminosities, the FUV radiation would populate the upper levels of the oxygen atom which would eventually contribute to the [Oi] lines. FUV pumping competes with collisions as an excitation mechanism of the [Oi] lines, and they each originate from a distinct region in the protostellar disk environment depending on the specifics of the hydrodynamical model that the simulation was based on. Consequently, the line strengths and shapes of [Oi] 6300 A and[Oi] 5577 A would be affected by the inclusion of FUV pumping in the radiation transport simulations.

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Ahmad Nemer, Jeremy Goodman, Lile Wang. 2020-08-24. The role of FUV Pumping in exciting the [Oi] lines in Protostellar Disks and Winds. https://doi.org/10.3847/2041-8213%2Fabc9b6

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