arXiv subjects

M. Hayakawa

Publications and source records attributed to M. Hayakawa.

44 records · Page 3Linked to original sources

arXiv1997

Pseudoscalar pole terms in the hadronic light-by-light scattering contribution to muon $ g - 2 $

The pseudoscalar pole contribution is the dominant source of the $ {\cal O}(α^3) $ hadronic light-by-light scattering effect in muon $g - 2$. We have examined this contribution taking account of the off-shell structure of the pseudoscalar-photon-photon anomaly vertex deduced from available experimental data. Our work leads to an improved estimate, $ -79.2 (15.4) \times 10^{-11}$, for the total hadronic light-by-light scattering contribution to the muon $g - 2$.

hep-ph↗

arXiv1997

Mass hierarchy from compositeness hierarchy in supersymmetric gauge theory

The possibility that the mass hierarchy is intimately associated with the compositeness level of the matters is proposed in supersymmetric gauge theory. This implies, for instance, that the preons constituting top quark consists of the ``prepreons'' binded by the same gauge force making the charm quark out of another preons. The exemplifying toy model illustrates how the hierarchy in the yukawa coupling constants in the up-quark sector is generated from the underlying gauge dynamics. It is also indicated that the incorporation of down-type quarks as elementary objects leads to unpleasant results generically. Thus all the quarks as well as the leptons must also be regarded as composite in the present approach.

hep-ph↗

arXiv1997

Measurement of CPT violation in the neutral kaon system

The basic feature of the measurement of CPT violation in the neutral kaon system is overviewed beginning with noting the physical implication of CPT violation. After describing $K^0-\bar{K}^0$ system at length, how CPT test is possible is illustrated with adding a few remarks on it.

hep-ph↗

arXiv1996

Remarks on the Hadronic Effect in Muon $g-2$: Low Energy Behavior of $V^0 $-$π^+$ Scattering

The behavior of the $V^0$-$π^+$ scattering amplitude (where $V^0 = ρ^0 , ω$ , or $ϕ$) in the low pion momentum limit is studied motivated by its relevance to the theory of muon $g - 2$. Current algebra analysis shows that its S-wave component must vanish in the chiral limit under general physical assumptions. We confirm this result with various low energy models of vector meson. Our result justifies the calculation of the charged pion loop part of the hadronic light-by-light scattering contribution to muon $ g-2 $ within the framework of hidden local symmetry model of low energy hadron dynamics.

hep-ph↗

arXiv1996

Hadronic Light-by-light Scattering Contribution to Muon $ g - 2 $

The hadronic light-by-light scattering contribution to muon $g-2$ is examined based on the low energy effective theories of QCD, the Nambu-Jona-Lasinio model and hidden local symmetry approach, supplemented by a general information concerning the asymptotic behavior of QCD. Our result is $- 52 \times 10^{-11}$ with an uncertainty of $\pm 18 \times 10^{-11}$, which includes our best estimate of model dependence. This is within the expected measurement uncertainty of $40\times 10^{-11}$ in the forthcoming experiment at Brookhaven National Laboratory. Our result removes one of the main theoretical obstacles in verifying the existence of the weak contribution to the muon $g-2$.

hep-ph↗

arXiv1995

Hadronic Light-by-light Scattering Effect on Muon g-2

The hadronic light-by-light scattering contribution to muon $g-2$ is examined using low energy effective theories of QCD, the Nambu-Jona-Lasinio model and hidden local chiral symmetry, as guides. Our result is $- 36 \times 10^{-11}$ with an uncertainty of $\pm 16 \times 10^{-11}$, which includes our best estimate of model dependence. This is within the expected measurement uncertainty of $40\times 10^{-11}$ in the forthcoming experiment at Brookhaven National Laboratory. Our result removes one of the main theoretical obstacles in verifying the existence of the weak contribution to the muon $g-2$.

hep-ph↗

arXiv1993

Chiral Lagrangian with higher resonances and flavour $ SU(3) $ breaking

A chiral Lagrangian with $ SU(3) $ breaking and higher resonances is proposed. In this model, the $ SU(3) $ breaking structure in vector-pseudoscalar sector is realized with the decay constants of pseudoscalar mesons and the masses of vector mesons used as inputs. We examine whether the resulting $ SU(3) $ breaking effect in the charge radii of pseudoscalar mesons is consistent with the experimental facts.

hep-ph↗

arXiv1993

Searching for T,CP,CPT,and ΔS = ΔQ rule violations in the neutral K meson system - a guide

It is known that the existing experimental limit for$ CPT $ violation is rather poor; the 10 \% level at best. The $ \DSDQ $ rule is tested only up to 2 \%. In this note, we discuss the possibility of measuring $ T, CP, CPT $ and $ \DSDQ $ rule violations in the neutral $ K $ meson system. It is shown that not all the symmetry breaking parameters can be determined at a symmetric $ ϕ$ factory. Experiments with $ K^0 $ and $ \bar{K}^0 $ beams are needed to test all the symmetries.

hep-ph↗