Theoretical Nuclear Physics

小行星9509266 在相对论速度下的核-核碰撞中，可以创造出一块温度和密度与大爆炸后早期宇宙和中子星内部相似的物质。 在这个提议中，我们将使用有效拉格朗日量和基于量子色动力学的模型来研究这种热的稠密物质的性质。 特别是，强子质量和耦合在有限的密度和温度将进行研究，因为他们预计将显着修改中的介质。 在相对论输运模型中包括这些介质效应允许在现有加速器的能量下对重离子碰撞进行现实的描述。 由于物质中双轻子的相互作用相对较弱，因此对这些碰撞产生的双轻子的研究将提供关于热致密物质性质的直接信息。 奇异粒子的产生也将被研究，因为它们作为奇异守恒的结果提供了另一个有希望的热致密物质的探测器。 我们的长期目标是扩展相对论输运模型，包括夸克和胶子的自由度，使之能够描述在未来的相对论重离子对撞机中，夸克胶子等离子体预计将形成在初始阶段的核碰撞。这项拟议中的研究使得有可能确定夸克-胶子等离子体的存在并研究其性质。 ***

9509266 Ko In nucleus-nucleus collisions at relativistic velocities, a piece of matter with temperature and density similar to that in the early universe after the Big Bang and the interior of neutron stars can be created. In this proposal, we shall investigate the properties of this hot dense matter using both effective Lagrangians and models that are based on the quantum chrodynamics. In particular, hadron masses and couplings at finite densities and temperatures will be studied since they are expected to be significantly modified in a medium. Including these medium effects in the relativistic transport model allows a realistic description of heavy ion collisions at energies available from present accelerators. The study of dilepton production from these collisions will then provide direct information on the properties of the hot dense matter due to the relatively weak interactions of dileptons in matter. The production of strange particles will also be investigated as they offer another promising probe of the hot dense matter as a result of strangeness conservation. Our long range goal is to extend the relativistic transport model to include the quark and gluon degrees of freedom so that one can describe nuclear collisions at future relativistic heavy ion colliders in which a quark-gluon plasma is expected to be formed in the initial stage. the proposed study makes it possible to identify the existence of the quark-gluon plasma and to study its properties. ***