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arXiv · hep-ph/9710238

Dark Matter Predictions With Non-Universal Soft Breaking Masses

Abstract

The effect of non-universal SUSY soft breaking on predictions of dark matter detector event rates are surveyed for supergravity models with gravity mediated soft breaking. For universal soft breaking in the first two generations and tan(beta)<=20, non-universal effects can be characterized by four parameters (two for Higgs and two for third generation squarks) in addition to those of the minimal model (MSGM). These can increase or decrease event rates by a factor of 10-100 in the domain m_{χ_1^0}<60 GeV (χ_1^0= lightest neutralino) but produce generally small effects at higher masses. The value of the top mass and b->s+γbranching ratio eliminates most of the parameter space for μ<0, causing event rates for μ<0 to be a factor approximately 100 smaller than for mu>0. A correlation between large (small) event rates and small (large) b-> s+γbranching ratio is observed. The effect of future satellite (MAP and PLANCK) precision determinations of cosmological parameters on predicted event rates is examined for examples of the ΛCDM and νCDM models. It is seen that these could sharpen the event rate predictions and also restrict the allowed gaugino mass ranges, thus influencing predictions for accelerator SUSY searches.

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BibTeXRIS

R. Arnowitt. 1997-10-03. Dark Matter Predictions With Non-Universal Soft Breaking Masses. https://arxiv.org/abs/hep-ph/9710238

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