1998/04/06 by M. Laine, M. Shaposhnikov
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1016/s0550-3213(98)00474-x
published as Nucl.Phys.B532:376-404,1998 · 31 pages, 5 figures
arxiv created 1998/04/06 · openalex publication_date 1998/10/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
In theories with low energy supersymmetry breaking, the effective potential for squarks and sleptons has generically nearly flat directions, V(phi) ~ M4 (log(phi/M))n. This guarantees the existence of stable non-topological solitons, Q-balls, that carry large baryon number, B >> (M/mp)4, where mp is the proton mass. We study the behaviour of these objects in a high temperature plasma. We show that in an infinitely extended system with a finite density of the baryon charge, the equilibrium state is not homogeneous and contains Q-balls at any temperature. In a system with a finite volume, Q-balls evaporate at a volume dependent temperature. In the cosmological context, we formulate the conditions under which Q-balls, produced in the Early Universe, survive till the present time. Finally, we estimate the baryon to cold dark matter ratio in a cosmological scenario in which Q-balls are responsible for both the net baryon number of the Universe and its dark matter. We find out naturally the correct orders of magnitude for M ~ 1...10 TeV: η~ 10-10 (M/TeV)-2 (B/1026)-1/2.