Q-ball is a nontopological soliton whose stability is ensured by global U(1) symmetry. We study a Q-ball which arises in the Affleck-Dine mechanism for baryogenesis and consider its possible instability due to U(1) breaking term (A-term) indispensable for successful baryogenesis. It is found that the instability destroys the Q-ball if its growth rate exceeds inverse of the typical relaxation time scale of the Q-ball. However, the instability is not so strong as it obstructs the cosmological formation of the Q-balls.
|Number of pages||7|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2005 Jul 21|