Ohki, H., Fukaya, H., Hashimoto, S., Matsufuru, H., Noaki, J., Onogi, T., ...
We present a calculation of the nucleon sigma term on two-flavor QCD configurations with dynamical overlap fermions. We analyse the lattice data for the nucleon mass using the baryon chiral...
Pion vector and scalar form factors with dynamical overlap quarks (2008)
Kaneko, TWQCD Collaborations: T., Aoki, S., Chiu, T. W., Fukaya, H., Hashimoto, S., ...
We calculate the pion vector and scalar form factors in two-flavor QCD. Gauge configurations are generated with dynamical overlap quarks on a 16^3 x 32 lattice at a lattice spacing of 0.12 fm with...
Light meson spectrum with $N_f=2+1$ dynamical overlap fermions (2008)
Noaki, J., Aoki, S., Chiu, T. W., Fukaya, H., Hashimoto, S., Hsieh, T. H., ...
We report on a numerical simulation with 2+1 dynamical flavors of overlap fermions. We calculate pseudo-scalar masses and decay constants on a $16^3\times 48 \times (0.11 {\rm fm})^4$ lattice at five...
Topological susceptibility in (2+1)-flavor lattice QCD with overlap fermion (2008)
Chiu, T. W., Aoki, S., Hashimoto, S., Hsieh, T. H., Kaneko, T., Matsufuru, H., ...
We determine the topological susceptibility \chi_t in the topologically-trivial sector generated by lattice simulations of N_f = 2+1 QCD with overlap Dirac fermion, on a 16^3 x 48 lattice with...
Lattice calculation of strong coupling constant from vacuum polarization functions (2008)
Shintani, E., Aoki, S., Chiu, T. W., Hashimoto, S., Hsieh, T. H., Kaneko, T., ...
We calculate the vacuum polarization functions on the lattice with exact chiral symmetry. By matching the lattice data at large momentum scales with the perturbative expansion supplemented by...
Nucleon sigma term and strange quark content from lattice QCD with exact chiral symmetry (2008)
Ohki, H., Fukaya, H., Hashimoto, S., Kaneko, T., Matsufuru, H., Noaki, J., ...
We calculate the nucleon sigma term in two-flavor lattice QCD utilizing the Feynman-Hellman theorem. Both sea and valence quarks are described by the overlap fermion formulation, which preserves...
S-parameter and pseudo-Nambu-Goldstone boson mass from lattice QCD (2008)
Shintani, E., Aoki, S., Fukaya, H., Hashimoto, S., Kaneko, T., Matsufuru, H., ...
We present a lattice calculation of $L_{10}$, one of the low energy constants in Chiral Perturbation Theory, and the charged-neutral pion squared mass splitting, using dynamical overlap fermion....
Topological susceptibility in 2-flavor lattice QCD with fixed topology (2008)
Chiu, T. W., Aoki, S., Fukaya, H., Hashimoto, S., Hsieh, T. H., Kaneko, T., ...
We determine the topological susceptibility $ \chi_t $ in the trivial topological sector generated by lattice simulations of two-flavor QCD with overlap Dirac fermion, on a $16^3 \times 32$ lattice...
Convergence of the chiral expansion in two-flavor lattice QCD (2008)
Noaki, J., Aoki, S., Chiu, T. W., Fukaya, H., Hashimoto, S., Hsieh, T. H., ...
We test the convergence property of the chiral perturbation theory (ChPT) using a lattice QCD calculation of pion mass and decay constant with two dynamical quark flavors. The lattice calculation is...
Two-flavor QCD simulation with exact chiral symmetry (2008)
Aoki, JLQCD Collaboration: S., Fukaya, H., Hashimoto, S., Ishikawa, K-I., Kanaya, K., Kaneko, T., ...
We perform numerical simulations of lattice QCD with two flavors of dynamical overlap quarks, which have exact chiral symmetry on the lattice. While this fermion discretization is computationally...
B_K with two flavors of dynamical overlap fermions (2008)
Aoki, S., Fukaya, H., Hashimoto, S., Noaki, J., Kaneko, T., Matsufuru, H., ...
We present a two-flavor QCD calculation of $B_K$ on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm (or equivalently $a^{-1}\sim$1.67 GeV). Both valence and sea quarks are described by the overlap...
Lattice study of meson correlators in the epsilon-regime of two-flavor QCD (2007)
Fukaya, JLQCD Collaboration: H., Aoki, S., Hashimoto, S., Kaneko, T., Matsufuru, H., Noaki, J., ...
We calculate mesonic two-point functions in the epsilon-regime of two-flavor QCD on the lattice with exact chiral symmetry. We use gauge configurations of size 16^3 32 at the lattice spacing a \sim...
Meson correlators in the epsilon-regime of two-flavor lattice QCD (2007)
Aoki, S., Hashimoto, S., Kaneko, T., Matsufuru, H., Noaki, J., ...
We calculate the meson correlators in the $\epsilon$-regime of two-flavor QCD. On a $16^3\times 32$ lattice with $a\sim 0.11$ fm, the lattice simulations are performed with the dynamical overlap...
Lattice simulation of 2+1 flavors of overlap light quarks (2007)
Hashimoto, JLQCD Collaboration: S., Aoki, S., Fukaya, H., Kaneko, T., Matsufuru, H., Noaki, J., ...
We report on the status of the dynamical overlap QCD simulation project by the JLQCD collaboration. After completing two-flavor QCD simulation on a 16^3x32 lattice at lattice spacing a 0.12 fm, we...
Pion form factor from all-to-all propagators of overlap quarks (2007)
Kaneko, JLQCD Collaboration: T., Fukaya, H., Hashimoto, S., Matsufuru, H., Noaki, J., Onogi, T., ...
We report on our calculation of the pion electromagnetic form factor with two-flavors of dynamical overlap quarks. Gauge configurations are generated using the Iwasaki gauge action on a 16^3 \times...
Light meson spectrum with $N_f=2$ dynamical overlap fermions (2007)
Noaki, J., Aoki, S., Fukaya, H., Hashimoto, S., Kaneko, T., Matsufuru, H., ...
We present numerical simulation of QCD with two dynamical quark flavors described by the overlap fermion action on a $16^3\times 32\times (0.12 {\rm fm})^4$ lattice. We calculate pseudo-scalar masses...
Topological susceptibility in two-flavor lattice QCD with exact chiral symmetry (2007)
Aoki, S., Chiu, T. W., Fukaya, H., Hashimoto, S., Hsieh, T. H., Kaneko, T., ...
We determine the topological susceptibility $\chi_t$ in two-flavor QCD using the lattice simulations at a fixed topological sector. The topological charge density is unambiguously defined on the...
B_K with dynamical overlap fermions (2007)
Yamada, JLQCD Collaboration: N., Aoki, S., Fukaya, H., Hashimoto, S., Noaki, J., Kaneko, T., ...
We report on a calculation of $B_K$ with two-flavor dynamical overlap fermions on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm. The results are compared with the PQChPT prediction of quark mass...
Pion mass difference from vacuum polarization (2007)
Shintani, JLQCD Collaboration: E., Fukaya, H., Hashimoto, S., Matsufuru, H., Noaki, J., Onogi, T., ...
We calculate the electromagnetic contribution to the pion mass difference, $\Delta m^2_\pi=m^2_{\pi^+}-m^2_{\pi^0}$, in the chiral limit through the $VV-AA$ type vacuum polarization using...
Two-flavor lattice QCD in the epsilon-regime and chiral Random Matrix Theory (2007)
Fukaya, TWQCD Collaboration: H., Aoki, S., Chiu, T. W., Hashimoto, S., Kaneko, T., ...
The low-lying eigenvalue spectrum of the QCD Dirac operator in the epsilon-regime is expected to match with that of chiral Random Matrix Theory (ChRMT). We study this correspondence for the case...
Two-flavor lattice QCD simulation in the epsilon-regime with exact chiral symmetry (2007)
Fukaya, JLQCD Collaboration: H., Aoki, S., Chiu, T. W., Hashimoto, S., Kaneko, T., Matsufuru, H., ...
We perform lattice simulations of two-flavor QCD using Neuberger's overlap fermion, with which the exact chiral symmetry is realized at finite lattice spacings. The epsilon-regime is reached by...
Precision study of B^* B\pi coupling for the static heavy-light meson (2006)
Negishi, S., Matsufuru, H., Onogi, T.
We compute the B^*B\pi coupling \hat{g}_{\infty} for static heavy-light meson using all-to-all propagators. It is shown that low-mode averaging with 100 low-lying eigenmodes indeed improves the...
JLQCD's dynamical overlap project (2006)
Kaneko, JLQCD Collaboration: T., Aoki, S., Fukaya, H., Hashimoto, S., Ishikawa, K-I., Kanaya, K., ...
We present an overview of our project of large-scale simulations with dynamical overlap fermions. The first production run in two-flavor QCD is on-going using the Iwasaki gauge action on a 16^3...
Dynamical overlap fermions in the epsilon-regime (2006)
Fukaya, JLQCD Collaboration: H., Hashimoto, S., Kanaya, K., Kaneko, T., Matsufuru, H., Ogawa, K., ...
We report on the two-flavor QCD simulation in the epsilon-regime using the overlap fermion formulation. Sea quark mass is reduced to ~ 2 MeV on a 16^3x32 lattice with the lattice spacing ~ 0.11fm....
Dynamical overlap fermion at fixed topology (2006)
Hashimoto, JLQCD Collaboration: S., Aoki, S., Fukaya, H., Kanaya, K., Kaneko, T., Matsufuru, H., ...
We launched a project to perform dymanical fermion simulations using the overlap fermion formulation for sea quarks. In order to avoid the appearace of near-zero modes of the hermitian Wilson-Dirac...
Yamada, JLQCD Collaboration: N., Aoki, S., Fukaya, H., Hashimoto, S., Ishikawa, K-I., Kanaya, K., ...
We perform a systematic study of low-lying eigenmodes of $H_w$ with various gauge actions to find the optimal choice for dynamical overlap fermion simulations, with which one may achieve lower...
Lattice gauge action suppressing near-zero modes of H_W (2006)
Fukaya, JLQCD Collaboration: H., Hashimoto, S., Kaneko, T., Matsufuru, H., Onogi, T., ...
We propose a lattice action including unphysical Wilson fermions with a negative mass m_0 of the order of the inverse lattice spacing. With this action, the exact zero mode of the hermitian...
Topology conserving gauge action and the overlap-Dirac operator (2005)
Fukaya, H, Hashimoto, S, Hirohashi, T, Ogawa, K, Onogi, T
We apply the topology conserving gauge action proposed by Luescher to the four-dimensional lattice QCD simulation in the quenched approximation. With this gauge action the topological charge is...
Topology conserving gauge action and the overlap-Dirac operator (2005)
Fukaya, H., Hashimoto, S., Hirohashi, T., Ogawa, K., Onogi, T.
We apply the topology conserving gauge action proposed by Luescher to the four-dimensional lattice QCD simulation in the quenched approximation. With this gauge action the topological charge is...
Overlap fermion with the topology conserving gauge action (2005)
Fukaya, H., Hashimoto, S., Hirohashi, T., Matsufuru, H., Ogawa, K., Onogi, T.
We investigate the distribution of low-lying eigenmodes of hermitian Wilson-Dirac operator, $H_W$, with the gauge action whose form is designed to avoid topology change, as well as with the standard...
Fukaya, H., Onogi, T., Hashimoto, S., Hirohashi, T., Ogawa, K.
The topology conserving gauge action proposed by Luescher is expected to reduce the number of non-smooth gauge configurations as well as the topology change compared to the conventional actions for...
Lattice QCD Study of the Pentaquark Baryons (2004)
Takahashi, T. T., Umeda, T., Onogi, T., Kunihiro, T.
We study the spin $\frac12$ hadronic state in quenched lattice QCD to search for a possible $S=+1$ pentaquark resonance. Simulations are carried out on $8^3\times 24$, $10^3\times 24$, $12^3\times...
Light hadron spectrum in 2+1 flavor full QCD by CP-PACS and JLQCD Collaborations (2004)
Ishikawa, T., Aoki, S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
CP-PACS and JLQCD Collaborations are carrying out a joint project of the 2+1 flavor full QCD with the RG-improved gauge action and the non-perturbatively ${\cal O}(a)$-improved Wilson quark action....
Physics at Super B Factory (2004)
Akeroyd, A. G., Bartel, W., Bondar, A., Browder, T. E., Drutskoy, A., Enari, Y., ...
This report presents the results of studies that investigate the physics reach at a Super B factory, an asymmetric-energy e^+e^- collider with a design luminosity of 5 x 10^35 cm^-2s^-1, which is...
Lattice QCD calculation of the proton decay matrix element in the continuum limit (2004)
Tsutsui, JLQCD Collaborations: N., Aoki, S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., ...
We present a quenched lattice QCD calculation of the \alpha and \beta parameters of the proton decay matrix element. The simulation is carried out using the Wilson quark action at three values of the...
Takeuchi, T., Onogi, T., Otagiri, T., Mizutani, U., Sato, H., Kato, K., ...
Electrical resistivity of Al_{82.6-x}Re_{17.4}Si_x (7≼x≼12) 1/1-1/1-1/1 approximants was discussed in terms of their electronic structure near the Fermi level and the local atomic arrangements....
Continuum limit of proton decay matrix elements in quenched lattice QCD (2003)
Tsutsui, JLQCD Collaborations: N., Aoki, S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., ...
We present a lattice QCD calculation of the parameters \alpha and \beta which are necessary in the theoretical estimation of the proton lifetime in grand unified theories (GUTs) using chiral...
B-Bbar mixing in unquenched lattice QCD (2003)
Aoki, JLQCD Collaboration: S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., Iwasaki, Y., ...
We present an unquenched lattice calculation for the $B^0-\bar{B}^0$ transition amplitude. The calculation, carried out at an inverse lattice spacing $1/a$ = 2.22(4) GeV, incorporates two flavors of...
Light hadron spectroscopy with two flavors of $O(a)$-improved dynamical quarks (2002)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We present a high statistics study of the light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Numerical simulations are carried out using the plaquette gauge action...
Heavy-light meson in anisotropic lattice QCD (2002)
Matsufuru, H., Harada, J., Onogi, T., Sugita, A.
We examine whether the $O(a)$ improved quark action on anisotropic lattices can be used as a framework for the heavy quark, which enables precision computation of matrix elements of heavy-light...
$B^0-\bar{B}^0$ mixing in quenched lattice QCD (2002)
Aoki, JLQCD Collaboration: S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., Iwasaki, Y., ...
We present our results of lattice calculations of $B$ parameters, which parameterize $\Delta B$=2 transition amplitudes together with the leptonic decay constant. Calculations are made in the...
I=2 Pion Scattering Length with the Wilson Fermion (2002)
Aoki, JLQCD Collaboration: S., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., Iwasaki, Y., ...
The calculation of the I=2 pion scattering length in quenched lattice QCD is revisited. The calculation is carried out with the Wilson fermion action employing L\"uscher's finite size scaling method...
Charmed hadron physics in quenched anisotropic lattice QCD (2002)
Harada, J., Matsufuru, H., Onogi, T., Sugita, A.
We investigate the anisotropic lattice with $O(a)$ improved quark action as a candidate of framework in which we can treat both the heavy and light quark region in the same manner and systematically...
Polynomial Hybrid Monte Carlo algorithm for lattice QCD with an odd number of flavors (2001)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We present a polynomial hybrid Monte Carlo (PHMC) algorithm for lattice QCD with odd numbers of flavors of O(a)-improved Wilson quark action. The algorithm makes use of the non-Hermitian Chebyshev...
Heavy quark expansion parameters from lattice NRQCD (2001)
Tsutsui, JLQCD Collaboration: N., Aoki, S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., ...
Using the lattice NRQCD action for heavy quark, we calculate the heavy quark expansion parameters $\mu_{\pi}^2$ and $\mu_G^2$ for heavy-light mesons and heavy-light-light baryons. The results are...
Exploration of sea quark effects in two-flavor QCD with the O(a)-improved Wilson quark action (2001)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We explore sea quark effects in the light hadron mass spectrum in a simulation of two-flavor QCD using the nonperturbatively O(a)-improved Wilson fermion action. In order to identify finite-size...
O(a) improved Wilson quark action on anisotropic lattice (2001)
Umeda, T., Matsufuru, H., Onogi, T.
The $O(a)$ improved Wilson quark action on the anisotropic lattice is investigated. We carry out numerical simulations in the quenched approximation at three values of lattice spacing...
One-loop renormalization of heavy-light currents (2001)
Harada, J., Hashimoto, S., Kronfeld, A. S., Onogi, T., Yamada, N.
We calculate the mass dependent renormalization factors of heavy-light bilinears at one-loop order of perturbation theory, when the heavy quark is treated with the Fermilab formalism. We present...
B meson B-parameters and the decay constant in two-flavor dynamical QCD (2001)
Yamada, JLQCD Collaboration: N., Aoki, S., Bulkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., ...
We present a two-flavor dynamical QCD calculation of the B meson B parameters and decay constant. We use NRQCD for heavy quark and the nonperturbatively O(a)-improved Wilson action for light quark at...
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
JLQCD collaboration recently started the $N_f=3$ QCD simulations with the $O(a)$-improved Wilson fermion action employing an exact fermion algorithm developed for odd number of quark flavors. It is...
An exact algorithm for three-flavor QCD with $O(a)$-improved Wilson fermions (2001)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We present an exact dynamical QCD simulation algorithm for the $O(a)$-improved Wilson fermion with odd number of flavors. Our algorithm is an extension of the non-Hermitian polynomials HMC algorithm...
Differential decay rate of $B \to \pi l \nu$ semileptonic decay with lattice NRQCD (2001)
Aoki, JLQCD Collaboration: S., Fukugita, M., Hashimoto, S., Ishizuka, N., Iwasaki, Y., ...
We present a lattice QCD calculation of $B\to \pi l \nu$ semileptonic decay form factors in the small pion recoil momentum region. The calculation is performed on a quenched $16^3 \times 48$ lattice...
CP Violation in Seesaw Model (2000)
Endoh, T., Morozumi, T., Onogi, T., Purwanto, A.
We study the structure of CP violating phases in the seesaw model. We find that the $3\times 6$ MNS matrix contains six independent phases, three of which are identified as a Dirac phase and two...
Differential decay rate for $B \to \pi l \nu$ semileptonic decays (2000)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We present our study on $B \to \pi l \nu$ semileptonic decay form factors with NRQCD action for heavy quark from a quenched lattice QCD simulation at $\beta$=5.9 on a $16^3\times 48$ lattice. We...
Light hadron spectroscopy with two flavors of O(a) improved dynamical quarks (2000)
Aoki, JLQCD Collaboration: S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., Ishizuka, N., ...
We report on our study of light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Simulations are made with the plaquette gauge action and the non-perturbatively $O(a)$...
B^0-\bar{B}^0 mixing with quenched lattice NRQCD (2000)
Yamada, JLQCD Collaboration: N., Aoki, S., Burkhalter, R., Fukugita, M., Hashimoto, S., Ishikawa, K-I., ...
We present our recent results for the B-parameters, which parameterize the \Delta B=2 transition amplitudes. Calculations are made in quenched QCD at \beta=5.7, 5.9, and 6.1, using NRQCD for heavy...
Perturbative renormalization of the $\Delta B=2$ four-quark operators in lattice NRQCD (2000)
Hashimoto, S., Ishikawa, K-I., Onogi, T., Sakamoto, M., Tsutsui, N., Yamada, N.
We present a perturbative calculation of the renormalization constants for the $\Delta B=2$ four-quark operators, which is needed to evaluate the bag parameters $B_B$ and $B_S$ in lattice QCD. The...