Possibility of baryon number violation at hot spots in relativistic heavy-ion collisions

It is possible that under certain situations, in a relativistic heavy-ion collision, partons may expand out forming a shell like structure. We analyze the process of hadronization in such a picture for the case when the quarkhadron transition is of first order, and argue that the inside region of such a shell must correspond to supercooled (to T = 0) deconfined vacuum. Hadrons from that region escape out, leaving a bubble of pure deconfined vacuum with large vacuum energy. This bubble undergoes relativistic collapse, with highly Lorentz contracted bubble walls, concentrating entire energy into extremely small regions. Eventually bubble walls collide, with the energy being released in the form of particle production. Thermalization of this system can lead to temperatures of the order of several GeV for RHIC energies, and may even exceed the electroweak transition temperature (∼ 100 GeV) for LHC. We discuss implications of such hot spots, most importantly about the possibility of observing sphaleron transitions and resulting baryon number violation in heavy-ion collisions at LHC. Even for RHIC, such high temperatures will have clear signals, in terms of very large PT partons, dileptons, and enhanced production of heavy quarks. Due to concentration of large energy at these hot spots, possibility of Higgs and top quark production may also arise. PACS numbers: 25.75.-q, 12.38.Mh, 98.80.Cq Typeset using REVTEX e-mail: [email protected] e-mail: [email protected] e-mail: [email protected]