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The One-Loop Correction to Heavy Dark Matter Annihilation

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 نشر من قبل Nicholas Rodd Dr
 تاريخ النشر 2016
  مجال البحث فيزياء
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We calculate the one-loop corrections to TeV scale dark matter annihilation in a model where the dark matter is described by an SU(2)$_L$ triplet of Majorana fermions, such as the wino. We use this framework to determine the high and low-scale MS-bar matching coefficients at both the dark matter and weak boson mass scales at one loop. Part of this calculation has previously been performed in the literature numerically; we find our analytic result differs from the earlier work and discuss potential origins of this disagreement. Our result is used to extend the dark matter annihilation rate to NLL (NLL+O($alpha_2$) corrections) which enables a precise determination of indirect detection signatures in present and upcoming experiments.

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