Chiral density waves driven by strong magnetic field and their dynamic properties

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K05346
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Aichi University of Education
• Principal Investigator: Abuki Hiroaki 愛知教育大学, 教育学部, 講師 (70378933)
• Research Collaborator: Nakano Eiji
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: QCD物性 / カイラル結晶

Outline of Final Research Achievements

Many exotic phases, including color superconductivity, condensations of mesons, and　quarkyonic phases, have been proposed for the ground state of super dense matter such　as realized in the core of neutron stars. In this study, we focus on one of them, namely the inhomogeneous chiral condensate. In particular, we include the effect of magnetic fields, and examine the possibility of several types of inhomogeneous chiral condensates and the conditions for their realizations. The main findings are the following.
1) Using a parity doublet model known to reproduce saturation properties of nuclear matter, we have shown that the onset of inhomogeneous chiral condensate is about five times the saturation density.
2) Adopting the Ginzburg-Landau action which should be valid in the vicinity of tricritical point of QCD in the chiral limit, we have shown that the dual chiral density wave should be stabilized in the presence of magnetic field at an arbitrary strength.

Free Research Field

素粒子・原子核・宇宙線・宇宙物理

Academic Significance and Societal Importance of the Research Achievements

中性子星の内部で実現すると考えられている密度領域において、双対カイラル密度波がたしかに実現しうることを示したことで、この新奇な相の天文学的帰結を探求する動機を提供したという点で、学術的意義は大きい。また、クォークの質量がゼロという極限の仮想的状況においてQCD相図上に存在することが強く示唆されている三重臨界点の近傍に、磁場という触媒によって磁場誘起型双対カイラル密度波が安定化する領域が広がることが示されたことで、研究は原始中性子星や連星中性子星合体等の物理を探求する段階に入ったと言える。はっきりとした今後の研究の方向性を与えたという意味で学術的意義は大きい。