Abstract
We study the formation of HCO+ and HC18O+ emission lines in the cloud L1544. The radiation transfer is modeled numerically, and the line intensities for different impact parameters are calculated. It is shown that a decrease in the abundances of the studied molecules toward the object center is necessary for the formation of the observed line profile in the optically thin case. We consider various hydrodynamic models allowing for compression, turbulence, and different types of cloud rotation and find a model ensuring the best agreement with the observational data. Our numerical simulations are indicative of nonuniform rotation in L1544. Assuming that the object is spherically symmetric, we estimate the density and velocity of the medium within the framework of the selected model.
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Troitsky, N.R., Lapinov, A.V. & Zamozdra, S.N. Radiation-Transfer Modeling of the Cloud L1544 in the HCO+ and HC18O+ Emission Lines. Radiophysics and Quantum Electronics 47, 77–84 (2004). https://doi.org/10.1023/B:RAQE.0000035690.09708.c1
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DOI: https://doi.org/10.1023/B:RAQE.0000035690.09708.c1