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Feedback and the Formation of Dwarf Galaxy Stellar Halos

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 نشر من قبل Greg Stinson
 تاريخ النشر 2009
  مجال البحث فيزياء
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 تأليف Greg Stinson




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Stellar population studies show that low mass galaxies in all environments exhibit stellar halos that are older and more spherically distributed than the main body of the galaxy. In some cases, there is a significant intermediate age component that extends beyond the young disk. We examine a suite of Smoothed Particle Hydrodynamic (SPH) simulations and find that elevated early star formation activity combined with supernova feedback can produce an extended stellar distribution that resembles these halos for model galaxies ranging from $v_{200}$ = 15 km s$^{-1}$ to 35 km s$^{-1}$, without the need for accretion of subhalos.



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