Low-energy lepton physics in the MRSSM: $(g-2{)}_{\mu }$, $\mu \to e\gamma$ and $\mu \to e$ conversion

Abstract

Low-energy lepton observables are discussed in the Minimal R-symmetric Supersymmetric Standard Model. We present comprehensive numerical analyses and the analytic one-loop results for $(g-2{)}_{\mu }$, $\mu \to e\gamma$, and $\mu \to e$ conversion. The interplay between the three observables is investigated as well as the parameter regions with large $g-2$. A striking difference to the MSSM is the absence of $\tan \beta$ enhancements; however we find smaller enhancements governed by MRSSM-specific R-Higgsino couplings ${\lambda }_d$ and ${\Lambda }_d$. As a result we find significant contributions to $g-2$ only in a small parameter space with several SUSY masses below $200$ GeV, compressed spectra and large ${\lambda }_d$, ${\Lambda }_d$. In this parameter space there is a correlation between all three considered observables. In the parameter region with small $(g-2{)}_{\mu }$ the SUSY masses can be larger and the correlation between $\mu \to e\gamma$ and $\mu \to e$ conversion is weak. Therefore already COMET Phase 1 has a promising sensitivity to the MRSSM.

49 pages, 14 figures; added comments about LHC exclusion limits + minor text adjustments, results unchanged; version published in JHEP