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arXiv · 1306.0085

Chemical evolution during the process of proto-star formation by considering a two dimensional hydrodynamic model

Ankan Das·Liton Majumdar·Sandip K. Chakrabarti·Sonali Chakrabarti
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Abstract

Chemical composition of a molecular cloud is highly sensitive to the physical properties of the cloud. In order to obtain the chemical composition around a star forming region, we carry out a two dimensional hydrodynamical simulation of the collapsing phase of a proto-star. A total variation diminishing scheme (TVD) is used to solve the set of equations governing hydrodynamics. This hydrodynamic code is capable of mimicking evolution of the physical properties during the formation of a proto-star. We couple our reasonably large gas-grain chemical network to study the chemical evolution during the collapsing phase of a proto-star. To have a realistic estimate of the abundances of bio-molecules in the interstellar medium, we include the recently calculated rate coefficients for the formation of several interstellar bio-molecules into our gas phase network. Chemical evolution is studied in detail by keeping grain at the constant temperature throughout the simulation as well as by using the temperature variation obtained from the hydrodynamical model. By considering a large gas-grain network with the sophisticated hydrodynamic model more realistic abundances are predicted. We find that the chemical composition are highly sensitive to the dynamic behavior of the collapsing cloud, specifically on the density and temperature distribution.

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Ankan Das, Liton Majumdar, Sandip K. Chakrabarti, Sonali Chakrabarti. 2013-06-01. Chemical evolution during the process of proto-star formation by considering a two dimensional hydrodynamic model. https://doi.org/10.1016/j.newast.2013.01.003

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