2005 Fiscal Year Final Research Report Summary
Dynamical Structure of the Quark-Gluon Plasma based on Lattice QCD with Bayesian Statistics
| Project/Area Number |
15540254
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Particle/Nuclear/Cosmic ray/Astro physics
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| Research Institution | The University of Tokyo |
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Principal Investigator |
HATSUDA Tetsuo The University of Tokyo, School of Science, Professor, 大学院理学系研究科, 教授 (20192700)
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| Co-Investigator(Kenkyū-buntansha) |
EJIRI Shinji The University of Tokyo, School of Science, Assistant Professor, 大学院理学系研究科, 助手 (10401176)
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| Project Period (FY) |
2003 – 2005
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| Keywords | quark-gluon plasma / Bayesian statistics / Maximum entropy method / color superconductivity / charmonium / phase transition / hadron physics |
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| Research Abstract |
Inside the quark-gluon plasma, the quark-anti-quark potential becomes weak due to the thermal Debye screening. As a result, the bound states composed of heavy-quarks melt down above certain critical temperature. However, the precise relation between the melting temperature and the critical temperature of the confinement-deconfinement phase transition.
We have carried out lattice QCD simulations to answer this problem and have found that heavy charmonium such as J/Psi can survive even up to 1.7 times the critical temperature. The large volume simulations as well as the use of the Bayesian statistics play essential role in this study.
In the interior of the neutron stars and quark stars, there may exist quark matter composed of deconfined quarks. Since there is always an attractive channel in the quark-quark interaction at the Fermi surface, quark matter is in the color superconducting state.
We have carried our Ginzburg-Landau analysis of the phase transition between the color superconducting state and the normal state and found that the phase transition is driven to first order due to the thermal fluctuation of the gluons.
We have applied the maximum entropy method to analyses the excited baryon spectra calculated on the lattice. It was found that the method can extract the position of the positive and negative excited states of the nucleon correctly. Also, the method is powerful enough to separate the physical spectra and the unphysical spectra due to lattice discretization.
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Research Products
(33 results)
