R-parity breaking phase transition in the susy singlet majoron model

Abstract

We consider thermal properties of the susy singlet majoron model. We compute the critical temperature $T_c$ and the subsequent reheating temperature $T_{\mathrm{RH}}$ for $R$-parity breaking. Succesful baryogenesis constrains the parameter space via the requirements that $T_c$ and $T_{\mathrm{RH}}$ are lower than the electroweak phase transition temperature. A further constraint is provided by requiring that the gauge singlet should be kinematically allowed to decay, in order not to have a matter dominated universe at the time of nucleosynthesis. We have made a detailed study of the parameter space and find an upper limit for the susy breaking scalar mass $\text{mm}\text{lsim}750(900)$ GeV if $\text{gluino}=100(1000)$ GeV, which is valid except for certain special values of the singlet sector parameters.

Comments: 9 pages LaTEX, 3 uuencoded figures