Quark Degree of Freedom and Meson Fields in Baryon Many-Body System

1.关于重子结构和核力--(1)用集体坐标方法精确地处理SU(3)×SU(3)Skyrme模型中的SU(3)v破缺，我们发现我们的方法特别有效地解释了重子多重子之间的质量分裂。(2)对于手征袋模型，我们研究了当系统被推广到包括其他介子，例如&lt；omega&gt；介子时，仅为pion情形构造的框架是如何工作的，并且发现袋内的Casimir效应在这种情况下也是重要的。(3)利用手征袋模型研究了核力问题。对于两个夸克层之间的相互作用，我们已经准确地处理了一个图解模型，现在我们的形式被扩展到研究现实中的重子-重子相互作用。关于高密度核物质中的相--(1)我们研究了包括重夸克在内的夸克物质的状态方程，发现由于QCD的渐近自由，夸克星是引力不稳定的。(2)对于热对称核物质中的中性介子凝聚，通过包含&lt；Delta&gt；(1232)，进行了考虑有效相互作用的Hartree-Fock计算，并讨论了它与高能H.I.碰撞现象的关系。(3)对于中性介子和带电介子的联合凝聚，我们采用了具有实际效应的手征对称方法，如等压子和重子-重子短程关联，研究了中子星的内部结构和冷却问题。此外，还讨论了凝聚中子星与毛刺现象的关系，并提出了解释船帆和克利布脉冲星毛刺现象的新机制。(4)研究了K-on凝聚问题，讨论了K-on凝聚对中子星冷却的影响。

1. On the baryon structure and nuclear force - (1) Treating the SU(3)v breaking in the SU(3) X SU(3) Skyrme model exactly within the collective coordinate method, we have found that our method is effective especially to explain the mass splitting among baryon multiplets. (2) As for the chiral bag model, we studied how the framework constructed for only pion case works well once system is generalized to include other mesons, e.g. <omega>mesons, and found that the Casimir effects inside the bag are important also in this case. (3) We studied the problem of nuclear force with the use of the chiral bag model. A schematic model has been treated exactly for interactin between two quark layers and now our formalism is extended to study realistic baryon-baryon interaction.2. On the phases in high-density nuclear matter - (1) We have examined equation of state for quark matter including heavy quarks and found that quark stars are gravitationally unstable due to the asymptotic freedom of QCD. (2) As for the neutral pion condensation in hot symmetric nuclear matter, a Hartree-Fock calculation with an effective interaction has been done by including <DELTA> (1232), and its relevance to the phenomena during highenergy H.I.collisions has been discussed. (3) As for the combined condensation of neutral and charged pions, a chiral symmetry approach with realistic effects such as isobars and baryon-baryon short-range correlations have been taken, and we studied interior structure and the cooling problem of neutron stars. Moreover, relation between <pi>-condensed neutron stars and glitch phenomena has been discussed and a new mechanism to explain those in Vela and Cleb pulsars has been proposed. (4) Problem of K-on condensation has been examined and its effects on the cooling of neutron stars have been discussed.