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Red Galaxies from Hot Halos in Cosmological Hydro Simulations

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 نشر من قبل Jared Gabor
 تاريخ النشر 2012
  مجال البحث فيزياء
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 تأليف Jared Gabor




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I highlight three results from cosmological hydrodynamic simulations that yield a realistic red sequence of galaxies: 1) Major galaxy mergers are not responsible for shutting off star-formation and forming the red sequence. Starvation in hot halos is. 2) Massive galaxies grow substantially (about a factor of 2 in mass) after being quenched, primarily via minor (1:5) mergers. 3) Hot halo quenching naturally explains why galaxies are red when they either (a) are massive or (b) live in dense environments.



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