120229024
Fermionic determinant and chiral anomalies
On obtient les anomalies chirales dans des changements d'un certain type de determinants regularises des operateurs de Dirac definis sur l'espace-temps euclidien R 2n sous des transformations chirales infinitesimales. On etudie une relation entre les anomalies chirales et la topologie de l'espace des operateurs de Dirac inversibles. Une possible modification du determinant regularise est etudiee en liaison avec le modele de Schwinger chiral
123591192
A Comment on Spontaneous Breaking of Chiral Symmetry
122057407
Regularized determinants for quantum field theories with fermions
A new type of regularized determinant for the ratio of two Dirac operators is presented. Some of its properties with application to the chiral anomaly are given.
121660455
Propagation of a Dirac particle. A path integral approach
Rigorous path integral formulas are given which represent, in two space‐time dimensions, the fundamental solution of the Cauchy problem for the Dirac equation as well as the retarded and advanced propagators for the Dirac particle. It is also shown that the theory can be applied to a free particle and a particle in a central electric field in four space‐time dimensions and reveals some aspects of the path integral. Heuristically discussed is the connection with the phase space path integral or Hamiltonian path integral.
124683607
Nuclear Matter in Neutron Stars. A Great Challenge in Nuclear Physics
Lack of our knowledge on the nuclear (hadronic) matter in the neutron star prevents us from understanding its internal structure. The elucidation of the neutron star matter is one of the most important and challenging subjects in nuclear physics today. The nuclear matter EOS (Equation Of State) which would describe pure neutron matter in the outer core of the neutron star is studied via various laboratory experiments particularly by using neutron-rich nuclei. Hyperons and/or kaons are expected to appear in the high density matter in the inner core, which is also experimentally investigated via hypernuclei and kaonic nuclei. Most of the EOS’s including hyperons or kaons lead to a serious discrepancy against the large mass (∼ 2M ) for the recently observed neutron stars, and resolution of this mystery requires new theoretical frameworks in nuclear physics which correctly describe high density matter, some of which may incorporate hadronic degrees of freedom with a deconfined quark matter phase.
120389194
In memory of Osamu Hashimoto
120162764
Study of Strangeness Photoproduction on the Neutron in the Threshold Region
Photoproduction of the neutral kaon on the deuteron has been investigated at the Research Center for Electron Photon Science, Tohoku University. We constructed the Neutral Kaon Spectrometer-2 for the detection of charged particles from the decay of the neutral kaon and the hyperon. We obtained a momentum distribution of K0 with the inclusive measurement. It was consistent with the previous measurement. The total cross section of γ + d → K0 + Λ + p was estimated from the measured integral cross section of γ + d → Λ + X. The total cross section with respect to the photon energy was compared with the theoretical calculations. It favored the Saclay-Lyon A model calculation with the ratio of the neutral to charged coupling constants of the axial-vector meson, K1, as ~ −1.5. The energy dependence and the magnitude of the total cross section were similar to the total cross section of γ + p → K+ Λ.
124892982
Investigation of Strangeness Photoproduction near the Threshold at ELPH, Tohoku University
Masashi Kaneta1, Brian Beckford1, Petr Bydžovský2, Takeshi Fujibayashi1, Takao Fujii1, Yu Fujii1, Kenta Futatsukawa1, Toshiyuki Gogami1, Yuncheng Han3, Osamu Hashimoto1 ∗, Kentaro Hirose4, Kenji Hosomi1, Ryotarou Honda1, Aran Iguchi1, Takatsugu Ishikawa4, Hiroki Kanda1, Yusuke Kaneko1, Yuma Kasai1, Taito Kawasaki1, Chigusa Kimura1, Shogo Kiyokawa1, Takeshi Koike1, Kazushige Maeda1, Nayuta Maruyama1, Masao Matsubara1, Koji Miwa1, Yohei Miyagi1, Sho Nagao1, Satoshi N. Nakamura1, Takashi Nishizawa1, Akira Okuyama1, Miloslav Sotona2,∗, Tadaaki Tamae4, Hirokazu Tamura1, Kyo Tsukada1, Nobu Terada1, Tieshan Wang3, Fumiya Yamamoto1, Takeshi O. Yamamoto1, and Hirohito Yamazaki4 (the NKS2 collaboration)