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The roles of ram-pressure stripping and minor mergers in evolution of galaxies

Takashi Okamoto·Masahiro Nagashima
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Abstract

We investigate environmental effects on evolution of bright cluster galaxies in a Lambda-dominated cold dark matter universe using a combination of dissipationless N-body simulations and a semi-analytic galaxy formation model. We incorporate effects of ram-pressure stripping (RPS) and minor merger-induced small starburst (minor burst) into our model. By considering minor burst, observed morphology-radius relation is successfully reproduced. When we do not consider minor burst, the RPS hardly increases the intermediate B/T population. In addition, the RPS and minor burst are not important for colours or star formation rates of galaxies in the cluster core if star formation time-scale is properly chosen, because the star formation is sufficiently suppressed by consumption of the cold gas. We also find that SF in bulge-dominated galaxies is mainly terminated by starburst induced by major mergers in all environments.

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Takashi Okamoto, Masahiro Nagashima. 2004-04-15. The roles of ram-pressure stripping and minor mergers in evolution of galaxies. https://doi.org/10.1017/s1743921304001164

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