Phase diagram at finite temperature and quark density in the strong coupling region of lattice QCD for colour SU(3)
We study the phase diagram of quark matter at finite temperature (T) and chemical potential (μ) in the strong coupling region of lattice QCD for colour SU(3). Baryon has effects to extend the hadron phase to a larger μ direction relative to T c at low temperatures in the strong coupling limit. With the l/g 2 corrections, T c is found to decrease rapidly as g decreases, and the shape of the phase diagram becomes closer to that expected in the real world.

title: Phase diagram at finite temperature and quark density in the strong coupling limit of lattice QCD for color SU(3)
abstract: We study the phase diagram of quark matter at finite temperature ($T$) and chemical potential ($\ensuremath{\mu}$) in the strong coupling limit of lattice QCD for color SU(3). We derive an analytical expression of the effective free energy as a function of $T$ and $\ensuremath{\mu}$, including baryon effects. The finite temperature effects are evaluated by integrating over the temporal link variable exactly in the Polyakov gauge with an antiperiodic boundary condition for fermions. The obtained phase diagram shows the first and the second order phase transition at low and high temperatures, respectively, and those are separated by the tricritical point in the chiral limit. Baryon has effects to reduce the effective free energy and to extend the hadron phase to a larger $\ensuremath{\mu}$ direction at low temperatures.

title: QCD critical point in the strong coupling lattice QCD and during black hole formation
abstract: We discuss the QCD phase diagram from two different point of view. We first investigate the phase diagram structure in the strong coupling lattice QCD with Polyakov loop effects, and show that the the chiral and Z_{N_c} deconfinement transition boundaries deviate at finite mu as suggested from large N_c arguments. Next we discuss the possibility to probe the QCD critical point during prompt black hole formation processes. The thermodynamical evolution during the black hole formation would result in quark matter formation, and the critical point in isospin asymmetric matter may be swept. (T,mu_B) region probed in heavy-ion collisions and the black hole formation processes covers most of the critical point locations predicted in recent lattice Monte-Carlo simulations and chiral effective models.

title: The Lowest (1/2+ and 0-) Hadron Masses and the Behavior of the Constituent Quarks
abstract: Masses of the lowest lying hadrons and the behavior of constituent quarks are discussed on the analysis of their electromagnetic properties, based on QCD. We find that light quarks (u and d) in the hadrons move with the velocity ::::O.Sc; s quark, with :$0.7c; c quark, with nearly 0.3c. Then we know that the confinement force, no matter what kind of confinement one prefers, does not mainly contribute to the hadron masses. It is also conjectured that Jv,-eJilu-d J;=;[v1,-,11[/Jc-sJ;=;Jv,-rJ/ lt-bl and m,:-::23 GeV on the assumption of the ex­ istence of the next layer. Masses of quarks, of which a hadron is built, are assumed arbitrarily to be from zero to infinity on the argument of various hadronic processes, but the constituent quark masses seem to be mu:-::330 and ms:-::510 (in units of MeV) in the inter­ mediate region at which the magnetic moments and the spectroscopy of hadrons are discussed.ll Can 7r have a mass of an order of one hundred MeV, when it is considered that it is a bound state of such quarks? How do the quarks behave in 7r or other hadrons? This note will con­ tribute to the analysis of the lowest lying hadron masses on the basis of the analysis of the electromagnetic properties by follow­ ing the previous discussions. 2>

title: Nonleptonic Hyperon Decay in the Quark Model
abstract: Nonleptonic hyperon and tr decays are discussed in the nonrelativistic quark model and the SU(6) theory, where we consider the pole diagram for quark. the four-body weak current­ current interaction J1 2 J3 1 and the meson exchange interaction_ We assume two models, and can explain the experiments for parity-violating and parity-conserving amplitudes of nonleptonic hyperon decays. In particular the L1I = 1/2 rule is derived, though the weak current-current interaction J1 2 J3 1 does not satisfy £11 = 1/2. As to the decay of tr two models predict the different ratio of r(SJ~A+K) and r(SJ~S+ll). One is consistent with experiment, the other forbids SJ~A+K.

title: One Gluon Exchange Contributions to Electromagnetic Mass Differences

title: Doubly charmed baryon masses and quark wave functions in baryons
abstract: We compute the masses of the ground state baryons and their spin excited states discussing quark wave functions in baryons. Doubly charmed baryon masses are given in the expected accuracy of \ifmmode\pm\else\textpm\fi{}10 MeV.

title: Electromagnetic Mass Differences of Charmed Particles