Infra-red stable fixed points of R-parity violating Yukawa couplings in supersymmetric models

Abstract

We investigate the infra-red stable fixed points of the Yukawa couplings in the minimal version of the supersymmetric standard model with R-parity violation. Retaining only the R-parity violating couplings of higher generations, we analytically study the solutions of the renormalization group equations of these couplings together with the top- and b-quark Yukawa couplings. We show that only the B-violating coupling ${\lambda }_{233}^{{}^{\prime \prime }}$ approaches a non-trivial infra-red stable fixed point, whereas all other non-trivial fixed point solutions are either unphysical or unstable in the infra-red region. However, this fixed point solution predicts a top-quark Yukawa coupling which is incompatible with the top quark mass for any value of $\tan \beta$.

Comments: Plain latex to be run twice, 12 pages. Replaced with version to appear in Physics Letters B