Particle production from disoriented chiral condensates described by a coherent state

Abstract

The production of pions and sigma mesons from disoriented chiral condensates (DCC's) of finite size is studied using the linear sigma model and a continuous mode coherent state. Two models are used to describe the decay of DCC's. One assumes instantaneous decay and the other assumes radiation from the surface. It is found that, for a spherical DCC of radius of several fm, possible signals related to the momentum spectrum, multiplicity, and the neutral-to-charged pion ratio will be completely masked by the background which dominates multiparticle production in nucleus-nucleus collisions at high energies unless an appropriate cut or binning in the phase space is made on an event-by-event basis. We propose that a signal of DCC's may manifest itself as an abnormal peak in the rapidity distribution if pions with medium and large transverse momenta are cut off. The smearing effect due to sigma meson decay on the characteristic distribution of neutral-to-charged pion ratio is also studied.