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arXiv · astro-ph/9807059

SPH code for dynamical and chemical evolution of disk galaxies

Abstract

The problem of chemical and dynamical evolution of galaxies is one of the most attracting and complex problems of modern astrophysics. Within the framework of the given work the standard dynamic Smoothed Particle Hydrodynamics (SPH) code (Monaghan J.J. 1992, ARAA, 30, 543) is noticeably expanded. Our investigation concernes with the changes and incorporation of new ideas into the algorithmic inclusion of Star Formation (SF) and Super Novae (SN) explosions in SPH (Berczik P. & Kravchuk S.G., 1996, ApSpSci, 245, 27). The proposed energy criterion for definition of a place and efficiency of SF results in the successfully explain Star Formation History (SFH) in isolated galaxies of different types. On the base of original ideas we expand a code in a more realistic way of the description of effects of return of a hot, chemical enriched gas in Interstellar Matter (ISM). In addition to the account of SNII, we offer the self-agreed account of SNIa and PN. This allows to describe not only the ISM content of $ O^{16} $ but also the content of $ Fe^{56} $. This model will allow to investigate adequately also a well known $ G - dwarf $ problem. In the frame of this approach we are able to reproduce the presently observed kinematics of star and gaseous components as well as their distributions and heavy element abundances. The developed model provide the realistic description of dynamics and chemical evolution of typical disk -- like galaxies over the Hubble timescale.

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Peter Berczik. 1998-07-07. SPH code for dynamical and chemical evolution of disk galaxies. https://arxiv.org/abs/astro-ph/9807059

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