High-density kaonic-proton matter (KPM) composed of Λ⁎≡K−p multiplets and its astrophysical connections

Abstract

We propose and examine a new form of high-density neutral composite of Λ⁎≡K−p=(su¯)⊗(uud), which may be called anti-Kaonic Proton Matter (KPM), or simply, Λ⁎-Matter, where substantial shrinkage of baryonic bound systems originating from the strong attraction of the (K¯N)I=0 interaction takes place, providing a ground-state neutral baryonic system with a large energy gap. The mass of an ensemble of (K−p)m, where m, the number of the K−p pair, becomes larger than m≈10, is predicted to drop down below that of its corresponding neutron ensemble, (n)m, since the attractive interaction is further increased by the Heitler–London type molecular covalency as well as by chiral symmetry restoration of the QCD vacuum. Since the seed clusters (K−p, K−pp and K−K−pp) are short-lived, the formation of such a stabilized relic ensemble, (K−p)m, may be conceived during the Big-Bang Quark Gluon Plasma (QGP) period in the early universe. At the final stage of baryogenesis a substantial amount of primordial (u¯,d¯)'s are transferred and captured into KPM, where the anti-quarks find places to survive forever. The expected KPM state may be cold, dense and neutral q¯q-hybrid (Quark Gluon Bound (QGB)) states, [s(u¯⊗u)ud]m, to which the relic of the disappearing anti-quarks plays an essential role as hidden components. KPM may also be produced during the formation and decay of neutron stars in connections with supernova explosions, and other forms may exist as strange quark matter in cosmic dusts.

Keywords

• Kaonic proton matter (KPM)
• Λ⁎(1405) strangelet
• Anti-quark hybrid matter
• Production in primordial quark–gluon plasma
• Strange quark matter
• Baryogenesis