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Induced theta-vacuum states in heavy ion collisions: a possible signature

K. Buckley·T. Fugleberg·A. Zhitnitsky
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Abstract

It has been suggested recently that an arbitrary induced theta-vacuum state could be created in heavy ion collisions. If such a state can be created, it would decay by various mechanisms to the fundamental theta=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 emission of pions, eta-mesons, and eta'-mesons. We will also present the spectrum of the produced particles in this non-zero theta background. We use the instantaneous perturbation theory for our estimates.

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K. Buckley, T. Fugleberg, A. Zhitnitsky. 2000-06-09. Induced theta-vacuum states in heavy ion collisions: a possible signature. https://doi.org/10.1103/physrevc.63.034602

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