Study of New Phases in High Density Strange Matter

高密度奇异物质新相的研究

• 批准号: 03804010
• 负责人: TAMAGAKI Ryozo
• 金额: $ 0.96万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03804010/
• 关键词: Strangeness; nuclear matter; quark matter; kaon cordensation; neutron star; phase transition; high density; quark model; クォーク物質; H粒子; バッグ模型; ストレィンジクォ-ク物貭; 飽和性; 構成子模型; 中性子星形成

In this project, new phases with large strangeness have been studied from various viewpoints, and we have obtained the main results as descibed below.1. Saturation property of strange quark matter (abbreviated to SQM) : In order to clarify the reality of E.Witten's conjecture on the possibility that SQM is the true hadronic ground state, studies with use of two QCD-motivated effective models (constituent quark model and bag model) have been done. The results by treating both finite and infinite systems unifiedly have shown the increase of energy per baryon E/A beyond the s-closed shell(A>6). This means that the existence of absolutely stable SQM is unlikely as far as the fundamental parameters built in such effective theories do not change substantially with incease of A.2. Kaon condensation : Realization mechanism of this phase has been studied in chiral symmetry approach. We have shown the remarkable increase of proton mixing with growth of K^- condensation and the possible occurrence of the direct URCA process for the symmetry energy with reasonable density dependence, and the resulting rapid cooling of neutron stars due to this process.3. Effects of hadoronic condensed phases with and without strangeness to supernovae matter and neutron star matter : Properties of condensed phases in supernovae matter just after birth of neutron stars and thermal and dynamical evolution have been studied. We have made clear that meson condensates and symmetry energy are strongly relevant to the whole processes from the birth to the well-cooled stage of neutron stars.4. Nuclear force in the systems with strangeness : Study of baryon structure and hyperon-nucleon interaction has progressed in the quark-cluster model by taking account of the breaking of the flavor SU(3) symmetry. This provides a base to study the interaction between H-particles which is indispensable for study of H-matter(strange matter with partial deconfinement).

在本项目中，我们从不同的角度对具有大奇异性的新相进行了研究，取得的主要结果如下：1。奇异夸克物质的饱和性质(简称SQM)：为了澄清E.Witten关于SQM是真正的强子基态的可能性的猜想的真实性，利用两个QCD激发的有效模型(组分夸克模型和袋模型)进行了研究。统一处理有限系统和无限系统的结果表明，在S闭壳(A&GT；6)之外，单位重子能量E/A增加。这意味着，只要建立在这种有效理论中的基本参数不会随着A2的增加而发生实质性变化，绝对稳定的SQM就不太可能存在。Kaon凝聚：用手征对称性方法研究了这一相的实现机制。结果表明，随着K^凝聚的增长，质子混合显著增加，并可能发生具有合理密度依赖性的对称能量的直接Urca过程，并由此导致中子星的快速冷却。有无奇异强子凝聚相对超新星物质和中子星物质的影响：研究了中子星诞生后超新星物质中凝聚相的性质以及热力学和动力学演化。我们已经明确了介子凝聚体和对称能与中子星从诞生到完全冷却阶段的整个过程有很强的相关性。具有奇异性的系统中的核力：重子结构和超子-核子相互作用的研究在夸克-团簇模型中取得了进展，考虑了味道SU(3)对称性的破坏。这为研究H物质(具有部分退禁闭的奇异物质)所必需的H粒子之间的相互作用提供了基础。

项目成果

Y.Fujiwara: "A Quark-Model Approach to LAMBDA N and SIGA N LS Forces with Flavor Symmetry Breaking" Phys.Lett.B318. 587-591 (1993)

Y.Fujiwara：“具有风味对称性破缺的 LAMBDA N 和 SIGA N LS 力的夸克模型方法”Phys.Lett.B318。

藤井宏次(H.Fujii): "Effects of weak Interaction on Kaon Condensation and Cooling of Neutron Stars" Nuclear Physics A. (in press). (1994)

H.Fujii：“弱相互作用对 Kaon 凝聚和中子星冷却的影响”核物理 A.（出版中）（1994 年）。

石井 充(M.Ishii): "One Gluon Exchange Effect on Saturation Property of Strange Quark Systems in the Bag Model" Progress of Theoretical Physics. 89. 657-677 (1993)

M.Ishii：“袋模型中奇异夸克系统饱和性质的一种胶子交换效应”理论物理进展 89. 657-677 (1993)。

武藤 巧(T.Muto): "Implications of Various Hadron Phases to Neutron Star Phenomena" Progress of Theoretical Physics Supplement. 112. 221-275 (1993)

T.Muto：“各种强子相对中子星现象的影响”理论物理进展增刊 112. 221-275 (1993)

藤原義和(Y.Fujiwara): "A Quark-Model Approach to ΛΝ and ΣΝ LS Forces with Flavor Symmetry Breaking" Physics Letters B. 318. 587-591 (1993)

Y.Fujiwara：“具有风味对称性破缺的 ΛΝ 和 ΣN LS 力的夸克模型方法”《物理快报》B. 318. 587-591 (1993)