Neutrino emission and initial evolution of axionic quark nuggets

Abstract

The axion quark nuggets introduced in the literature are a candidate for cold dark matter which, in addition, may be relevant in baryogenesis scenarios. The present work studies the evolution of these objects till they enter in the color superconducting phase. This evolution was already considered in [S. Ge, X. Liang, and A. Zhitnitsky, Phys. Rev. D 97, 043008 (2018).PRVDAQ2470-001010.1103/PhysRevD.97.043008], where it is concluded that a large chemical potential μ is induced on the bulk of the object. That work takes the baryon number accumulated at the domain wall surrounding the object as predominant, and suggests that internal and external fluxes are compensated in such a way that they not modify considerably the dynamics of the object if they are neglected. In the present work the possibility that the bulk contribution to the baryon number may be relevant at initial stages, and that the object may emit a large amount of neutrinos due to quark-antiquark annihilations is taken into account. This results into a more violent contraction of the object and perhaps a more effective cooling. The outcome is that the formed objects may have an smaller size. Even taking into account these corrections, it is concluded that the cosmological applications of these objects are not spoiled. These applications are discussed along the text.