R-Parity Violation and Peccei-Quinn Symmetry in GUTS

Abstract

We address the question whether it is possible in GUTs to obtain R-parity violation with a large $\Delta L/\Delta B$ hierarchy of strengths so that the proton is stable while phenomenologically interesting $L$-violation is present. We consider versions of SU(5) with a built-in Peccei-Quinn symmetry spontaneously broken at an intermediate scale. The P-Q symmetry and the field content guarantee a large suppression of the effective $B$-violating terms by a factor ${\Lambda }_{PQ}^3/M_P{M}_X^2$ while the effective $L$-violating terms stay large.

Comments: 8 pages, no figures