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arXiv · 2212.10752

Modelling the CO streamers in the explosive ejection of Orion BN/KL region

Ary Rodríguez-González·Pedro Ruben Rivera-Ortiz·Antonio Castellanos-Ramírez·Alejandro C. Raga·Liliana Hernández-Martínez·Jorge Cantó·Luis A. Zapata·Fátima Robles-Valdez
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Abstract

We present reactive gasdynamic, axisymmetric simulations of dense, high velocity clumps for modelling the CO streamers observed in Orion BN/KL. We have considered 15 chemical species, a cooling function for atomic and molecular gas, and heating through cosmic rays. Our numerical simulations explore different ejection velocities, interstellar medium density configurations, and CO content. Using the CO density and temperature, we have calculated the CO ($J=2\to1$) emissivity, and have built CO maps and spatially resolved line profiles, allowing us to see the CO emitting regions of the streamers and to obtain position velocity diagrams to compare with observations. We find that in order to reproduce the images and line profiles of the BN/KL CO streamers and H$_2$ fingers, we need to have clumps that first travel within a dense cloud core, and then emerge into a lower-density environment.

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Ary Rodríguez-González, Pedro Ruben Rivera-Ortiz, Antonio Castellanos-Ramírez, Alejandro C. Raga, Liliana Hernández-Martínez, Jorge Cantó, Luis A. Zapata, Fátima Robles-Valdez. 2022-12-21. Modelling the CO streamers in the explosive ejection of Orion BN/KL region. https://doi.org/10.1093/mnras%2Fstac3793

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