Large Higgs Boson Exchange Contribution in Three-Body Neutralino Decays

TL;DR

This paper demonstrates that Higgs boson exchange can significantly enhance three-body neutralino decay rates, especially in specific parameter regions, impacting branching ratios even with small tan(beta).

Contribution

It reveals the substantial role of Higgs exchange in neutralino decays under certain conditions, expanding understanding of supersymmetric decay processes.

Findings

Higgs exchange can dominate three-body neutralino decays.

Branching ratios for specific decays are significantly increased.

Enhancement occurs even with small tan(beta) values.

Abstract

We show that the Higgs boson exchange contribution can be large in three-body decays of neutralinos even in the case of small tan(beta). This enlarges the branching ratios for the decays neutralino_2 -> neutralino_1 b \bar{b} and neutralino_2 -> neutralino_1 tau- tau+. This is the case in the region of the parameter space where the two lightest neutralinos are gaugino-like, the sfermions are heavier than 300 GeV, and m_A0 = 200 GeV or smaller.