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Multi-spot ignition in type Ia supernova models

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 نشر من قبل Friedrich Konrad Roepke
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف F. K. Roepke




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We present a systematic survey of the capabilities of type Ia supernova explosion models starting from a number of flame seeds distributed around the center of the white dwarf star. To this end we greatly improved the resolution of the numerical simulations in the initial stages. This novel numerical approach facilitates a detailed study of multi-spot ignition scenarios with up to hundreds of ignition sparks. Two-dimensional simulations are shown to be inappropriate to study the effects of initial flame configurations. Based on a set of three-dimensional models, we conclude that multi-spot ignition scenarios may improve type Ia supernova models towards better agreement with observations. The achievable effect reaches a maximum at a limited number of flame ignition kernels as shown by the numerical models and corroborated by a simple dimensional analysis.



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