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Non Thermal Neutralino Production in Deflected Anomaly Mediation

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 نشر من قبل Andrea Lionetto
 تاريخ النشر 2007
  مجال البحث فيزياء
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 تأليف A. M. Lionetto




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We study the effects of a non thermal neutralino production, due to the late decay in the early universe of a single modulus field, in the context of the deflected anomaly mediated scenario. In the regime in which the average number of neutralino produced in each modulus decaying process is $bar{N}_{{rm LSP}}ll 1$ also models with a thermal relic density below WMAP data became acceptable models. We find out that these models belong to three different classes with the common feature that the low thermal relic density is entirely due to coannihilation effects. The neutralino annihilation cross section for these classes of models is not particularly high compared with the highest cross sections attainable in the generic framework of the MSSM. Hence the detection prospects either by direct or indirect WIMP search experiments are not encouraging.



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