Periodic structure in nuclear matter

Abstract

The properties of nuclear matter are studied in the framework of quantum hadrodynamics. Assuming an o-meson field, periodic in space, a self-consistent set of equations is derived in the mean-field approximation for the description of nucleons interacting via U-meson and w-meson fields. Solutions of these self-consistent equations have been found: The baryon density is constant in space, however, the baryon current density is periodic. This high density phase of nuclear matter can be produced by anisotropic external pressure, occurring, e.g., in relativistic heavy ion reactions. The self-consistent fields developing beyond the instability limit have a special screw symmetry. In the presence of such an o field, the energy spectrum of the relativistic nucleons exhibits allowed and forbidden bands, similar to the energy spectrum of the electrons in solids. PACS number(s): 21.65. + f

Recent Progress in Quantum Hadrodynamics

“…The interesting possibility of the transition of nuclear matter into a "Peierls' type" of periodic structure is investigated in the RMFT in [Lo92a,Lo94a].…”

“…Properties of neutron stars are examined within a similar RMFT framework in [Ma92c] and within DBHF theory in [Hu94]. The interesting possibility of the transition of nuclear matter into a "Peierls' type" of periodic structure is investigated in the RMFT in [Lo92a,Lo94a].…”

Anisotropic pressure and hyperons in neutron stars

“…Furthermore, it has been shown that at high density the nuclear matter pressure can also be anisotropic (see for example Refs. [42][43]. Since the pioneer work of Bowers and Liang, 44 there have been many works devoted to studies of anisotropic spherical symmetric configurations.…”

Formation of an ordered phase in neutron star matter

“…Whereas the idea of solidification of pure neutron matter considered in the seventies [1] was abandoned, other mechanisms have received attention lately: pion condensation [2], confinement of protons [3] by the repulsive character of the in-medium n-p interaction, ordering of a mixed quarkhadron phase in a way reminiscent of the neutron drip phase in the surface layers [4], etc. (See also [5,6,7]. )…”