Bounds onR-parity violating couplings at the weak scale and at the GUT scale

Abstract

We analyse bounds on trilinear R-parity violating couplings at the unification scale by renormalising the weak scale bounds. We derive unification scale upper bounds upon the couplings which are broadly independent of the fermion mass texture assumed. The R-parity violating couplings are factors of two to five more severely bounded at the unification scale than at the electroweak scale. In the presence of quark mixing, a few of the bounds are orders of magnitude stronger than their weak scale counterparts due to new R-parity violating operators being induced in the renormalisation between high and low scales. These induced bounds are fermion mass texture dependent. New bounds upon the weak scale couplings are obtained by the requirement of perturbativity between the weak and unification scales. A comprehensive set of the latest limits is included.

SUSY R-parity violating contributions to the width differences forD−D̄ andBd,s−B̄d,ssystems

“…As for the contributions from λ ′′ , from the constraint |λ ′′ 132 λ ′′ * 232 | < ∼ 3.1 × 10 −3 [21] , λ ′′ 112 , λ ′′ 121 < ∼ 2 × 10 −9 and λ ′′ 131 < 10 −4 [18], we find that λ ′′ contributions are small, less than 10 −4 .…”

“…For the interference term due to the SM with λ ′ term, we have not found direct constraint on the appropriate combination of the λ ′ terms. We therefore use individual constraints from [18] …”

Mass spectrum in R-parity violating minimal supergravity and benchmark points

“…[7,51,52]. In Table I we show the largest allowed coupling in the five "classes" of couplings for scalar masses of 100 GeV.…”

Soft RPV through the baryon portal

“…this effective scalar-fermion coupling is ruled out by precision flavor constraints, which require λ ∼ < 10 −7 for light flavors [15][16][17]. However, if these terms are generated effectively through a heavy mediator of mass M that ensures A ∼ m 2 S /M , then the amount of RPV is controlled dynamically.…”