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Overmerging in N-body simulations

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 نشر من قبل Eelco van Kampen
 تاريخ النشر 2000
  مجال البحث فيزياء
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 تأليف Eelco van Kampen




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The aim of this paper is to clarify the notion and cause of overmerging in N-body simulations, and to present analytical estimates for its timescale. Overmerging is the disruption of subhaloes within embedding haloes due to {it numerical} problems connected with the discreteness of N-body dynamics. It is shown that the process responsible for overmerging is particle-subhalo two-body heating. Various solutions to the overmerging problem are discussed



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