Energy release due to antineutrino untrapping from hot quark stars

Abstract

An equation of state for 2-flavor quark matter (QM) with diquark condensation under the conditions for compact stars -$β$-equilibrium, charge and color neutrality- is presented. Trapped antineutrinos prevent the formation of the diquark condensate at moderate densities above a critical value of the antineutrino chemical potential $μ_{\bar ν_e}^c$. The following consequences are presented: 1) The star develops a 2-phase structure ($μ_{\bar ν_e}\geq μ_{\bar ν_e}^c$): a color superconducting QM core and a normal QM shell. 2)During the cooling, when the temperature is small enough ($T<1$ MeV) the antineutrino mean free path becomes larger than the thickness of the normal QM shell and the antineutrinos get untrapped in a sudden burst. The energy release is estimated as $\simeq 10^{52}$ erg and an antineutrino pulse is expected to be observed.

10 pages, 6 figures (8 ps files and 3 epsi files), rotating_pr.sty and ws-procs9x6.cls files. Submitted for the Conference Proceedings of the KIAS-APCTP International Symposium in Astro-Hadron Physics Compact Stars: Quest for New States of Dense Matter, Nov. 10-14, 2003 in Seoul, Korea