English
Related papers

Related papers: Kl3 and pion form factors using partially twisted …

200 papers

The charge form factor of the pion is calculated in lattice QCD. The non-perturbatively improved Sheikholeslami-Wohlert action is used together with the $\mathcal{O}(a)$ improved vector current. Other choices for the current are examined.…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. Koch , E. Laermann

We present the calculation of the $K_{l3}$ form factors with $N_f = 2 + 1$ nonperturbatively $O(a)$-improved Wilson quark action and Iwasaki gauge action at the physical point on a large volume of (10.9 fm)$^3$ at one lattice spacing of $a…

We present a new calculation of the K->pi semileptonic form factor at zero momentum transfer in domain wall lattice QCD with Nf=2+1 dynamical quark flavours. By using partially twisted boundary conditions we simulate directly at the…

A calculation of the semi--leptonic decays of the kaon ($K_{l3}$) is presented. The results are direct predictions of a covariant model of the pion and kaon introduced earlier by Ito, Buck, Gross. The weak form factors for $K_{l3}$ are…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrei Afanasev , W. W. Buck

We present a calculation of the scalar, vector and tensor pion and kaon form factors using one ensemble of two degenerate light, a strange and a charm quark ($N_f=2+1+1$) of maximally twisted mass fermions with clover improvement. The quark…

We calculate the kaon semileptonic form factors in lattice QCD with three flavors of dynamical overlap quarks. Gauge ensembles are generated at pion masses as low as 290 MeV and at a strange quark mass near its physical value. We precisely…

High Energy Physics - Lattice · Physics 2012-11-28 JLQCD Collaboration , T. Kaneko , S. Aoki , G. Cossu , X. Feng , H. Fukaya , S. Hashimoto , J. Noaki , T. Onogi

We use a method to calculate the hadron's charge radius without model-dependent momentum extrapolations. The method does not require the additional quark propagator inversions on the twisted boundary conditions or the computation of the…

High Energy Physics - Lattice · Physics 2020-04-01 Xu Feng , Yang Fu , Lu-Chang Jin

We calculate the electromagnetic form factor of the pion in quenched lattice QCD. The non-perturbatively improved Sheikoleslami-Wohlert lattice action is used together with the consistently O(a) improved current. We calculate the pion form…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. H. Koch , E. Laermann

A calculation of the semi--leptonic decays of the kaon ($K_{l3}$) is presented. The results are direct predictions of a covariant model of the pion and kaon introduced earlier by Ito, Buck, Gross. The weak form factors for $K_{l3}$ are…

High Energy Physics - Phenomenology · Physics 2014-11-17 Andrei Afanasev , W. W. Buck

We investigate the vector and scalar form factors relevant for K_{\ell 3} semileptonic decays using maximally twisted-mass fermions with two flavors of dynamical quarks (N_f = 2). The simulations cover pion masses as light as 260 MeV and…

High Energy Physics - Lattice · Physics 2010-12-17 V. Lubicz , F. Mescia , L. Orifici , S. Simula , C. Tarantino

The pion form factor is calculated using quenched twisted mass QCD with beta=6.0 and maximal twisting angle omega=pi/2. Two pion masses and several values of momentum transfer are considered. The momentum averaging procedure of Frezzotti…

High Energy Physics - Lattice · Physics 2009-11-10 Abdou M. Abdel-Rehim , Randy Lewis

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Anisovich , D. Melikhov , V. Nikonov

The two gravitational form factors of the pion, $A^{\pi}(t)$ and $D^{\pi}(t)$, are computed as functions of the momentum transfer squared $t$ in the kinematic region $0\leq -t< 2~\text{GeV}^2$ on a lattice QCD ensemble with quark masses…

High Energy Physics - Lattice · Physics 2023-12-12 Daniel C. Hackett , Patrick R. Oare , Dimitra A. Pefkou , Phiala E. Shanahan

We compute the electromagnetic form factor of the pion using non-perturbatively O(a) improved Wilson fermions. The calculations are done for a wide range of pion masses and lattice spacings. We check for finite size effects by repeating…

The electromagnetic pion form factor, $F_\pi(q^2)$, is calculated for spacelike-$q^2$ in impulse approximation using a confining quark propagator, $S$, and a dressed quark-photon vertex, $\Gamma_\mu$, obtained from realistic,…

High Energy Physics - Phenomenology · Physics 2010-03-04 Craig D. Roberts

The CKM matrix element $|V_{us}|$ can be extracted from the experimental measurement of semileptonic $K\to\pi$ decays. The determination depends on theory input for the corresponding vector form factor in QCD. We present a preliminary…

High Energy Physics - Lattice · Physics 2012-12-14 Peter A. Boyle , Jonathan M. Flynn , Andreas Jüttner , Christopher Sachrajda , Karthee Sivalingam , James M. Zanotti

We present new lattice results of the K -> pion semileptonic form factors obtained from simulations with two flavors of dynamical twisted-mass fermions, using pion masses as light as 260 MeV. Our main result is f+(0) = 0.9560 (84), which,…

High Energy Physics - Lattice · Physics 2019-08-13 V. Lubicz , F. Mescia , S. Simula , C. Tarantino

We present a precise calculation of the pion form factor using overlap fermions on seven ensembles of 2+1-flavor domain-wall configurations with pion masses varying from 139 to 340 MeV. Taking advantage of the fast Fourier transform and…

High Energy Physics - Phenomenology · Physics 2021-10-13 Gen Wang , Jian Liang , Terrence Draper , Keh-Fei Liu , Yi-Bo Yang

We calculate the pion and kaon electromagnetic form factors in finite volume for a generic momentum transfer in space-like region, using SU(3) chiral perturbation theory. To this end, we first find the hadronic matrix element in a new form…

High Energy Physics - Phenomenology · Physics 2016-04-15 Karim Ghorbani

We investigate the utility of partially twisted boundary conditions in lattice calculations of meson observables. For dynamical simulations, we show that the pion dispersion relation is modified by volume effects. In the isospin limit, we…

High Energy Physics - Lattice · Physics 2008-11-26 F. -J. Jiang , B. C. Tiburzi