Neutralino Proton Cross Sections For Dark Matter In SUGRA And D-BRANE Models

TL;DR

This paper compares neutralino-proton cross sections across various supersymmetric models, identifying parameter regions detectable by current dark matter experiments and analyzing the effects of CP violation and coannihilation.

Contribution

It provides a comprehensive analysis of neutralino-proton cross sections in mSUGRA, nonuniversal SUGRA, and D-brane models, including the impact of CP phases and new coannihilation regions.

Findings

Detectors probe parts of the parameter space for tanβ > 25 in mSUGRA.

Nonuniversal models can have cross sections 10-100 times larger or smaller than universal models.

CP violating phases reduce cross sections by a factor of 2-3.

Abstract

Neutralino proton cross sections are examined for models with R-parity invariance with universal soft breaking (mSUGRA) models, nonuniversal SUGRA models, and D-brane models. The region of parameter space where current dark matter detectors are sensitive, i.e. $1\times 10^{-6}$ pb, is examined. For mSUGRA models, detectors are sampling parts of the parametr space for tan$\beta >\sim 25$. The nonuniversal models can achieve cross sections that are a factor of 10-100 bigger or smaller then the universal one and in the former case sample regions tan$\beta >\sim 4$. The D-brane models considered require tan$\beta >\sim 15$. The inclusion of CP violating phases reduces the cross section by a factor of $\sim$ 2-3 (but also requires considerable fine tuning at the GUT scale). The expected particle spectra at accelerators are examined and seen to differ for each model. Three new regions of possible coannihilation are noted.