The Experts below are selected from a list of 240 Experts worldwide ranked by ideXlab platform
Yoshinori Akaishi - One of the best experts on this subject based on the ideXlab platform.
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Structure of K - pp System and Super-Strong Nuclear Force by Migrating K - Meson:. its Theoretical Background
International Journal of Modern Physics A, 2009Co-Authors: Yoshinori Akaishi, Toshimitsu YamazakiAbstract:We have studied the structure of K-pp by solving this system in a variational method, starting from the ansatz that Λ* = Λ(1405) is a K-p quasi-bound state. The structure of K-pp reveals a molecular feature, namely, the K- in Λ* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. Deeply bound Nuclear systems are formed by this "super-strong" Nuclear Force due to migrating real bosons a la Heitler-London-Heisenberg, which overcompensates the stiff Nuclear incompressibility. Theoretical background of our phenomenological interaction is discussed, in connection with "decaying-state" description of kaonic Nuclear clusters, concerning the effective interaction based on chiral SU(3) dynamics. It is of virtual importance to determine whether the Λ* mass is 1405 MeV or 1420 MeV. It is found that a K- absorption at rest in 3He provides a testing ground better than that in 4He.
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super strong Nuclear Force caused by migrating kbar mesons revival of the heitler london heisenberg scheme in kaonic Nuclear clusters
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2007Co-Authors: Toshimitsu Yamazaki, Yoshinori AkaishiAbstract:We have studied the structure of K- pp comprehensively by solving this three-body system in a variational method, starting from the Ansatz that the Λ (1405) resonance (≡ Λ*) is a K- p bound state. The structure of K- pp reveals a molecular feature, namely, the K- in Λ* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound Kbar Nuclear systems are formed by "super strong" Nuclear Force due to migrating real bosonic particles Kbar a la Heitler-London-Heisenberg, whereas the normal Nuclear Force is caused by mediating virtual mesons. We have shown that the elementary process, p + p → K+ + Λ* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Λ* by the involved proton, since the Λ*-p system exists as a compact doorway state propagating to K-pp. (Contributed by Toshimitsu YAMAZAKI, M.J.A.)
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Super strong Nuclear Force caused by migrating Kbar mesons - Revival of the Heitler-London-Heisenberg scheme in kaonic Nuclear clusters
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2007Co-Authors: Toshimitsu Yamazaki, Yoshinori AkaishiAbstract:We have studied the structure of K- pp comprehensively by solving this three-body system in a variational method, starting from the Ansatz that the Lambda(1405) resonance (~ Lambda*) is a K-p bound state. The structure of K-pp reveals a molecular feature, namely, the K- in Lambda* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound Kbar Nuclear systems are formed by ``super strong" Nuclear Force due to migrating real bosonic particles Kbar a la Heitler-London-Heisenberg, whereas the normal Nuclear Force is caused by mediating virtual pions. We have shown that the elementary process, p + p --> K+ + Lambda* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Lambda* by the involved proton, since the Lambda*-p system exists as a compact doorway state propagating to K-pp.
Toshimitsu Yamazaki - One of the best experts on this subject based on the ideXlab platform.
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Structure of K - pp System and Super-Strong Nuclear Force by Migrating K - Meson:. its Theoretical Background
International Journal of Modern Physics A, 2009Co-Authors: Yoshinori Akaishi, Toshimitsu YamazakiAbstract:We have studied the structure of K-pp by solving this system in a variational method, starting from the ansatz that Λ* = Λ(1405) is a K-p quasi-bound state. The structure of K-pp reveals a molecular feature, namely, the K- in Λ* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. Deeply bound Nuclear systems are formed by this "super-strong" Nuclear Force due to migrating real bosons a la Heitler-London-Heisenberg, which overcompensates the stiff Nuclear incompressibility. Theoretical background of our phenomenological interaction is discussed, in connection with "decaying-state" description of kaonic Nuclear clusters, concerning the effective interaction based on chiral SU(3) dynamics. It is of virtual importance to determine whether the Λ* mass is 1405 MeV or 1420 MeV. It is found that a K- absorption at rest in 3He provides a testing ground better than that in 4He.
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super strong Nuclear Force caused by migrating kbar mesons revival of the heitler london heisenberg scheme in kaonic Nuclear clusters
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2007Co-Authors: Toshimitsu Yamazaki, Yoshinori AkaishiAbstract:We have studied the structure of K- pp comprehensively by solving this three-body system in a variational method, starting from the Ansatz that the Λ (1405) resonance (≡ Λ*) is a K- p bound state. The structure of K- pp reveals a molecular feature, namely, the K- in Λ* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound Kbar Nuclear systems are formed by "super strong" Nuclear Force due to migrating real bosonic particles Kbar a la Heitler-London-Heisenberg, whereas the normal Nuclear Force is caused by mediating virtual mesons. We have shown that the elementary process, p + p → K+ + Λ* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Λ* by the involved proton, since the Λ*-p system exists as a compact doorway state propagating to K-pp. (Contributed by Toshimitsu YAMAZAKI, M.J.A.)
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Super strong Nuclear Force caused by migrating Kbar mesons - Revival of the Heitler-London-Heisenberg scheme in kaonic Nuclear clusters
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2007Co-Authors: Toshimitsu Yamazaki, Yoshinori AkaishiAbstract:We have studied the structure of K- pp comprehensively by solving this three-body system in a variational method, starting from the Ansatz that the Lambda(1405) resonance (~ Lambda*) is a K-p bound state. The structure of K-pp reveals a molecular feature, namely, the K- in Lambda* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound Kbar Nuclear systems are formed by ``super strong" Nuclear Force due to migrating real bosonic particles Kbar a la Heitler-London-Heisenberg, whereas the normal Nuclear Force is caused by mediating virtual pions. We have shown that the elementary process, p + p --> K+ + Lambda* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Lambda* by the involved proton, since the Lambda*-p system exists as a compact doorway state propagating to K-pp.
Makoto Oka - One of the best experts on this subject based on the ideXlab platform.
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Origin of the short-range part of generalized two- and three-body Nuclear Force
Nuclear Physics A, 2012Co-Authors: Makoto OkaAbstract:Abstract Origin of the short-range baryon–baryon interactions is discussed from the quark substructure viewpoints of baryons. It is pointed out that the generalized Nuclear Force, recently obtained from the lattice QCD calculations, can be interpreted at short distances by the combinatory effects of the Pauli exclusion principle and the color–magnetic spin–spin interactions among the quarks. Classifications according to the spin-flavor SU(6) symmetry representations give us a general guidance on the features of the short-range interactions. The SU(6) analysis of the three-body baryon interactions reveals that the genuine three-body Force is repulsive at short distances due to the quark antisymmetrization.
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Erratum: Quark model analysis of the charge symmetry breaking in Nuclear Force [ Phys. Rev. C 68, 024006 (2003)]
Physical Review C, 2004Co-Authors: Takashi Nasu, Makoto Oka, Sachiko TakeuchiAbstract:In order to investigate the charge symmetry breaking (CSB) in the short range part of the Nuclear Force, we calculate the difference of the masses of the neutron and the proton, $\Delta {\rm M}$, the difference of the scattering lengths of the p-p and n-n scatterings, $\Delta a$, and the difference of the analyzing power of the proton and the neutron in the n-p scattering, $\Delta A(\theta)$, by a quark model. In the present model the sources of CSB are the mass difference of the up and down quarks and the electromagnetic interaction. We investigate how much each of them contributes to $\Delta {\rm M}$, $\Delta a$ and $\Delta A(\theta)$. It is found that the contribution of CSB of the short range part in the Nuclear Force is large enough to explain the observed $\Delta A(\theta)$, while $\Delta a$ is rather underestimated.Comment: 26 pages,6 figure
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Quark model analysis of the charge symmetry breaking in Nuclear Force
Physical Review C, 2003Co-Authors: Takashi Nasu, Makoto Oka, Sachiko TakeuchiAbstract:In order to investigate the charge symmetry breaking (CSB) in the short range part of the Nuclear Force, we calculate the difference of the masses of the neutron and the proton, $\Delta {\rm M}$, the difference of the scattering lengths of the p-p and n-n scatterings, $\Delta a$, and the difference of the analyzing power of the proton and the neutron in the n-p scattering, $\Delta A(\theta)$, by a quark model. In the present model the sources of CSB are the mass difference of the up and down quarks and the electromagnetic interaction. We investigate how much each of them contributes to $\Delta {\rm M}$, $\Delta a$ and $\Delta A(\theta)$. It is found that the contribution of CSB of the short range part in the Nuclear Force is large enough to explain the observed $\Delta A(\theta)$, while $\Delta a$ is rather underestimated.
Koji Hashimoto - One of the best experts on this subject based on the ideXlab platform.
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Nuclear Force from String Theory
Nuclear Physics, 2010Co-Authors: Koji HashimotoAbstract:Abstract Recent “technology” called holography, or gauge/string duality (AdS/CFT correspondence) found in string theory, makes it possible to compute various quantities of strongly coupled gauge theories. This technology was applied to QCD, and it was found that it describes surprisingly well important properties of low energy QCD, the hadron physics. We apply it further to Nuclear physics. In this talk, I review a part of the developments of the holographic QCD, and show a computation of Nuclear Force at short distance, derived using the holographic QCD, which was done in collaboration with T. Sakai and S. Sugimoto [K. Hashimoto, T. Sakai, and S. Sugimoto, “Holographic Baryons: Static Properties and Form Factors from Gauge/String Duality,” Prog. Theor. Phys. 120 (2008) 1093–1137, arXiv:0806.3122 [hep-th] ; K. Hashimoto, T. Sakai, and S. Sugimoto, “Nuclear Force from String Theory,” arXiv:0901.4449 [hep-th] ]. (This talk was presented at Hyp-X conference at J-PARC, on 25th September, 2009.)
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Nuclear Force from String Theory
Progress of Theoretical Physics, 2009Co-Authors: Koji Hashimoto, Tadakatsu Sakai, Shigeki SugimotoAbstract:We compute the Nuclear Force in a holographic model of QCD on the basis of a D4-D8 brane configuration in type IIA string theory. The repulsive core of nucleons is important in Nuclear physics, but its origin has not been well understood in strongly coupled QCD. We find that the string theory via gauge/string duality deduces this repulsive core at a short distance between nucleons. Since baryons in the model are realized as solitons given by Yang-Mills instanton configuration on flavor D8-branes, ADHM construction of two instantons probes well the nucleon interaction at short scale, which provides the Nuclear Force quantitatively. We obtain a central Force, as well as a tensor Force, which is strongly repulsive as suggested in experiments and lattice results. In particular, the nucleon-nucleon potential V (r) (as a function of the distance) scales as r−2, which is peculiar to the holographic model. We compare our results with the one-boson exchange model using the nucleon-nucleon-meson coupling obtained in our previous paper [K. Hashimoto, T. Sakai and S. Sugimoto, Prog. Theor. Phys. 120 (2008), 1093, arXiv:0806.3122].
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Nuclear Force from string theory
arXiv: High Energy Physics - Theory, 2009Co-Authors: Koji Hashimoto, Tadakatsu Sakai, Shigeki SugimotoAbstract:We compute Nuclear Force in a holographic model of QCD on the basis of a D4-D8 brane configuration in type IIA string theory. Repulsive core of nucleons is quite important in Nuclear physics, but its origin has not been well-understood in strongly-coupled QCD. We find that string theory via gauge/string duality deduces this repulsive core at short distance between nucleons. Since baryons in the model are realized as solitons given by Yang-Mills instanton configuration on flavor D8-branes, ADHM construction of two instantons probes well the nucleon interaction at short scale, which provides the Nuclear Force quantitatively. We obtain, as well as a tensor Force, a central Force which is strongly repulsive as suggested in experiments and lattice results. In particular, the nucleon-nucleon potential V(r) (as a function of the distance) scales as 1/r^2, which is peculiar to the holographic model. We compare our results with one-boson exchange model using the nucleon-nucleon-meson coupling obtained in our previous paper (arXiv:0806.3122).
John F. Donoghue - One of the best experts on this subject based on the ideXlab platform.
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Sigma exchange in the Nuclear Force and effective field theory
Physics Letters B, 2006Co-Authors: John F. DonoghueAbstract:AbstractIn the phenomenological description of the Nuclear interaction an important role is traditionally played by the exchange of a scalar I=0 meson, the sigma, of mass 500–600 MeV, which however is not seen clearly in the particle spectrum and which has a very ambiguous status in QCD. I show that a remarkably simple and reasonably controlled combination of ingredients can reproduce the features of this part of the Nuclear Force. The use of chiral perturbation theory calculations for two pion exchange supplemented by the Omnes function for pion rescattering suffices to reproduce the magnitude and shape of the exchange of a supposed σ particle. I also attempt to relate this description to the contact interaction that enters more modern descriptions of the internucleon interaction
