New Messenger Sector for Gauge Mediated Supersymmetry Breaking

We propose a new class of gauge mediated supersymmetry breaking models where the standard model gauge group is embedded into the gauge group $SU(2)L\times U(1){I_{3R}}\times U(1)_{B-L}$[or$SU(2)_L\times SU(2)R\times U(1){B-L}$] at the supersymmetry breaking scale ${\mathrm{\Lambda }}_S$. The messenger sector in these models can consist of color singlet but $U(1{)}_{I_{3R}}$ and $U(1{)}_{B-L}$ nonsinglet fields. The distinguishing feature of these models are (i)exact R-parity conservation, (ii) nonvanishing neutrino masses and (iii) a unified hidden and messenger sector potential. The simplest version of these models predicts the existence of light gluinos which can however be made heavier by a simple modification of the supersymmetry breaking sector.