Induced theta-vacuum states in heavy ion collisions: A possible signature - art. no. 034602

It has been suggested recently [K. Buckley, T. Fugleberg, and A. Zhitnitsky , Phys. Rev. Lett. 84, 4814 (2000)] that an arbitrary, induced theta -vacuu m state (theta (ind)) could be created in heavy-ion collisions. If such a s tate can be created, it would decay by various mechanisms to the theta (fun d)=0 state which is the true ground state of our world. In the following we will discuss the possibility of studying this unusual state through the em ission of pions. eta mesons, and eta' mesons. We will also present the spec trum of the produced particles in this nonzero theta background. We use the instantaneous perturbation theory for our estimates.