Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.109.111808

Language：English   Publishing type：Research paper (scientific journal)  

We determine the masses of light quarks by computing the light pseudo-scalar bosons via lattice QCD + QED. We also show that the origin of mass difference between proton and neutron, which is the source of nucleosynthesis, can be obtained from the first principle of quantum field theory.

Language：English   Publishing type：Research paper (scientific journal)  

The paper presents a detailed account of the evaluation of the electron anomalous magnetic moment, which arises from 6354 number of Feynman diagrams without closed lepton loops. The most precise value of the fine structure constant is also presented.

DOI： 10.1103/PhysRevD.91.033006

Language：English   Publishing type：Research paper (scientific journal)  

Theoretical computation of the tenth-order QED contribution to lepton g-2 is required for the most accurate determination of fine structure constant, strength of electromagnetic interaction. This needs computation of 12,672 number of complicated Feynman diagrams. It may cost you over 700 years if you write correct numerical programs for this computation. The goal of our group started our project to complete this computation within about five years three years ago by developing automation of almost whole computations. The paper is concerned with the remained part of this automation: treatment of infrared divergence from practical point of view.

Language：English   Publishing type：Research paper (scientific journal)  

The author find that the value of the eighth-order QED contribution to the anomalous magnetic moment reported previously is incorrect
and present its revised value.

Language：English   Publishing type：Research paper (scientific journal)  

The effect of sea quark electromagnetic charge on meson masses is investigated, and first results for full QED+QCD low-energy constants are presented. The electromagnetic charge for sea quarks is incorporated in quenched QED+full QCD lattice simulations by a reweighting method. The reweighting factor, which connects quenched and unquenched QED, is estimated using a stochastic method on 2+1 flavor dynamical domain-wall quark ensembles.

DOI： 10.1103/PhysRevLett.109.072002

Language：English   Publishing type：Research paper (scientific journal)  

The finite volume effect is one of systematic errors contained in the hadronic quantities measured in the lattice (QCD + QED) simulations. We construct QED on finite volume and determine the size of this effect from the low energy effective theory of QCD and QED.

Language：English   Publishing type：Research paper (scientific journal)  

We study the running gauge coupling constant of ten-flavor QCD by the lattice simulation. We give an evidence that the theyr possesses an infrared fixed point.

Language：English   Publishing type：Research paper (scientific journal)  

This paper reports the value for the magnitude of the magnetic dipole moment of a single electron to an accuracy of 1/1,000,000,000,000. It is well-known that an electron carries an electric charge. Together with its nonzero spin, this electric charge induces the magnetic dipole. The magnitude of the magnetic dipole moment can be calculated based on quantum electrodynamics (QED). We carry out the eighth-order perturbative calculation in QED. Using the latest value of magnetic dipole moment
measured by a Harvard group, we obtain the best value for the fine structure constant, which represents the magnitude of the elementary process
for the electric force.

Language：English   Publishing type：Research paper (scientific journal)  

We determine the values of up and down quarks from the lattice (QCD + QED) simulations formulated with domain wall fermions.

Language：English   Publishing type：Research paper (scientific journal)  

We computed the contribution to lepton g-2
which is induced through the eighth-order one-particle irreducible corrections to the vacuum polarization function by numerical means.

DOI： 10.1103/PhysRevD.83.053003

Language：English   Publishing type：Research paper (scientific journal)  

This paper reports the result of our evaluation of the tenth-order QED correction to the lepton g-2 from Feynman diagrams which have sixth-order light-by-light-scattering subdiagrams, none of whose vertices couple to the external magnetic field. The gauge-invariant set of these diagrams, called Set II(e), consists of 180 vertex diagrams.

Language：English   Publishing type：Research paper (scientific journal)  

We have evaluated the contribution to the anomalous magnetic moment of the electron from six tenth-order Feynman diagrams which contain eighth-order vacuum-polarization function formed by two light-by-light scattering diagrams connected by three photons. The integrals are constructed by two different methods. In the first method the subtractive counter terms are used to deal with ultraviolet (UV) singularities together with the requirement of gauge-invariance. In the second method, the Ward-Takahashi identity is applied to the light-by-light scattering amplitudes to eliminate UV singularities. Numerical evaluation confirms that the two methods are consistent with each other within their numerical uncertainties.

Language：English   Publishing type：Research paper (scientific journal)  

We computed the contribution of tenth-order QED correction to lepton g-2, caused by the Feynman diagrams which are obtained as the fourth-order radiative correction to the sixth-order light-by-light scattering subdiagram.

Language：English   Publishing type：Research paper (scientific journal)  

We report the results for the tenth-order QED contribution to the electron g-2 and the muon g-2, induced from the Feynman diagrams which are obtained by inserting sixth-order vacuum polarization subdiagrams into the fourth-order vertex diagrams.

DOI： 10.1103/PhysRevD.83.053002

Language：English   Publishing type：Research paper (scientific journal)  

We report the results for the tenth-order QED contribution to the electron g-2 and the muon g-2, induced from the Feynman diagrams which are obtained by inserting vacuum polarizations into the sixth-order vertex diagrams.

DOI： 10.1103/PhysRevD.84.053003

Language：English   Publishing type：Research paper (scientific journal)  

This paper reports the tenth-order QED contribution to the g-2 of electron and muon from two gauge-invariant sets: Set I(g) and Set I(h). In the case of electron g-2, Set I(g) consists of nine Feynman diagrams which have a fourth-order vacuum-polarization loop containing another fourth-order vacuum-polarization loop. Set I(h) consists of 30 Feynman diagrams which have a proper sixth-order vacuum-polarization loop containing a second-order vacuum-polarization loop.

Language：English   Publishing type：Research paper (scientific journal)  

We report the results for the tenth-order QED contribution to the lepton g-2, induced from the Feynman diagrams which are obtained by inserting the vacuum polarization subdiagram into the eighth-order vertex diagrams.

DOI： 10.1103/PhysRevD.85.033007

Language：English   Publishing type：Research paper (scientific journal)  

We report the results for the tenth-order QED contribution to the electron g-2 and the muon g-2, induced from the Feynman diagrams which are obtained by inserting the light-by-light scattering subdiagrams into the sixth-order vertex diagrams.

DOI： 10.1103/PhysRevD.85.093013

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physrep.2020.07.006

Other Link： https://arxiv.org/pdf/2006.04822.pdf

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physrep.2020.07.006

Web of Science

DOI： 10.1103/PhysRevLett.124.132002

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.96.034515

arXiv

Language：English   Publishing type：Research paper (scientific journal)  

arXiv

Authorship：Lead author   Language：English  

For reliable comparison of the standard model prediction to the muon g-2 with its experimental value, the hadronic light-by-light scattering (HLbL) contribution must be calculated by lattice QCD simulation. HLbL contribution has many types of disconnected-type diagrams. Here, we start with recalling the point that must be taken care of in every method to calculate them by lattice QCD, and present one concrete method called nonperturbative QED method.

arXiv

Language：English  

We will describe how lattice methods are well-suited to provide a first-principle's result for the hadronic light by light contribution, the various numerical strategies that are presently being used to evaluate it, our current results and the important remaining challenges which must be overcome.

arXiv

Language：English  

arXiv

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.88.094506

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.88.094504

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

In this review, we summarize the results of our numerical work carried out over nearly ten years on the complete determination of the 10th-order contribution to the anomalous magnetic moments of leptons in the perturbation theory of quantum electrodynamics. Our approach is based on a reorganized renormalization method in which no divergent quantities appear explicitly in any part of the calculation, which is crucial for the feasibility of numerical integration. The enormous number of 10th-order diagrams and the complexity of the renormalization procedure are such that we could not have handled this problem without the development of an automated code-generating algorithm. The systematic approach to these problems is described in some detail.

DOI： 10.1093/ptep/pts030

Language：English   Publishing type：Research paper (scientific journal)  

After a brief self-contained introduction to the muon anomalous magnetic momen, we review the status of lattice calculations of the hadronic vacuum polarization contribution and present first results from lattice QCD for the hadronic light-by-light scattering contribution. The signal for the latter is consistent with model calculations. While encouraging, the statistical error is large and systematic errors are mostly uncontrolled. The method is applied first to pure QED as a check.

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We study the dynamics of SU(2) gauge theory with six Dirac fermions by means of lattice simulation to investigate if they are appropriate to realization of electroweak symmetry breaking. The discrete analogue of beta function for the running coupling constant defined under the Schrödinger functional boundary condition are computed on the lattices up to linear size of L/a = 24 and preclude the existence of infrared fixed point below g2 ~ 7.6. Gluonic observables such as heavy quark potential, string tension, Polyakov loop suggest that the target system is in the confining phase even in the massless quark limit.

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