Affleck-Dine baryogenesis with R-parity violation

TL;DR

This paper explores how the Affleck-Dine mechanism can generate the universe's baryon asymmetry within supersymmetric models with R-parity violation, highlighting parameter ranges where this explanation is viable.

Contribution

It demonstrates that baryogenesis via the Affleck-Dine mechanism is feasible with small R-parity violating couplings and heavy gravitinos, and discusses Q-ball formation and evolution in this context.

Findings

Baryon asymmetry can be explained with R-parity violation couplings between 10^{-9} and 10^{-6}.

Q-balls play a crucial role in the baryogenesis process and their stability depends on the environment.

Larger R-parity violating couplings tend to destroy Q-balls and wash out baryon asymmetry.

Abstract

We investigate whether the baryon asymmetry of the universe is explained in the framework of the supersymmetric extension of the Standard Model with R-parity violating interactions. It is shown that the Affleck-Dine mechanism naturally works via a trilinear interaction $LLE^c$, $LQD^c$, or $U^cD^cD^c$, if the magnitude of the coupling corresponding to the operator $\lambda$, $\lambda'$, or $\lambda''$ is sufficiently small. The formation of Q-balls and their subsequent evolution are also discussed. The present baryon asymmetry can be explained in the parameter region where R-parity is mildly violated $10^{-9}\lesssim\lambda,\lambda',\lambda''\lesssim 10^{-6}$ and the mass of the gravitino is relatively heavy $m_{3/2}\gtrsim 10^4\mathrm{GeV}$. On the other hand, it is difficult to explain the present baryon asymmetry for larger values of R-parity violating couplings $\lambda,\lambda',\lambda''\gtrsim 10^{-5}$, since Q-balls are likely to be destructed in the thermal environment and the primordial baryon number is washed away.