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We compute the hadronic matrix elements of the four-quark operators relevant for $K^0-{\bar K^0}$ mixing beyond the Standard Model. Our results are from lattice QCD simulations with $n_f=2+1$ flavours of domain-wall fermion, which exhibit…

High Energy Physics - Lattice · Physics 2016-11-08 Nicolas Garron , Renwick J. Hudspith , Andrew T. Lytle

We present results for the nucleon electromagnetic form factors using an ensemble of maximally twisted mass clover-improved fermions with pion mass of about 130 MeV. We use multiple sink-source separations and three analysis methods to…

We present a lattice calculation of the charged/neutral pion mass difference $M_{\pi^{+}}-M_{\pi^{0}}$ at order $\mathcal{O}(\alpha_{em})$ using the gauge configurations produced by the Extended Twisted Mass Collaboration with $N_{f}=2+1+1$…

High Energy Physics - Lattice · Physics 2022-07-20 R. Frezzotti , G. Gagliardi , V. Lubicz , G. Martinelli , F. Sanfilippo , S. Simula

We present the first lattice Nf=2+1+1 determination of the tensor form factor $f_T^{D \pi(K)}(q^2)$ corresponding to the semileptonic and rare $D \to \pi(K)$ decays as a function of the squared 4-momentum transfer $q^2$. Together with our…

High Energy Physics - Lattice · Physics 2018-08-08 V. Lubicz , L. Riggio , G. Salerno , S. Simula , C. Tarantino

The pion form factor is computed using quenched twisted mass QCD and the GMRES-DR matrix inverter. The momentum averaging procedure of Frezzotti and Rossi is used to remove leading lattice spacing artifacts, and numerical results for the…

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

We use recent data on K^+ -> pi^+e^+e^-, together with known values for the pion form factor, to derive the kaon electromagnetic form factor for 0 <q^2 <0.125 (GeV/c)^2. The results are then compared with predictions of the Linear sigma…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Lowe , M. D. Scadron

We present a lattice determination of the vector and scalar form factors of the $D \to \pi(K) \ell \nu$ semileptonic decays, which are relevant for the extraction of the CKM matrix elements $|V_{cd}|$ and $|V_{cs}|$ from experimental data.…

High Energy Physics - Lattice · Physics 2019-10-24 V. Lubicz , L. Riggio , G. Salerno , S. Simula , C. Tarantino

We report a lattice calculation of nucleon forward matrix elements on a $48^3 \times 96$ lattice at the physical pion mass and a spatial size of 5.5 fm. The $2+1$ flavor dynamical fermion configurations are generated with domain-wall…

High Energy Physics - Lattice · Physics 2017-02-16 Keh-Fei Liu , Jian Liang , Yi-Bo Yang

We review two lattice calculations involving charm hadrons: a determination of the vector and scalar form factors of the semileptonic $D \to \pi \ell \nu$ decays, which are relevant for the extraction of the CKM matrix element $\lvert…

High Energy Physics - Lattice · Physics 2017-02-02 Lorenzo Riggio , Giorgio Salerno

We present results on the electroweak form factors and on the lower moments of parton distributions of the nucleon, within lattice QCD using two dynamical flavors of degenerate twisted mass fermions. Results are obtained on lattices with…

High Energy Physics - Lattice · Physics 2012-01-04 C. Alexandrou , M. Brinet , J. Carbonell , M. Constantinou , P. Guichon , P. A. Harraud , K. Jansen , C. Kallidonis , T. Korzec , M. Papinutto

Results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation are presented. We work with two different lattice volumes up to a spatial size of 2.4 fm at a lattice spacing of…

High Energy Physics - Lattice · Physics 2008-11-26 Stefano Capitani , Christof Gattringer , C. B. Lang

We present a determination of the ratio of kaon and pion leptonic decay constants in isosymmetric QCD (isoQCD), $f_K / f_\pi$, making use of the gauge ensembles produced by the Extended Twisted Mass Collaboration (ETMC) with $N_f = 2 + 1 +…

We compute the leading non-analytic quark mass dependence of the matrix elements of isovector twist-2 operators between octet baryon states in quenched QCD using quenched chiral perturbation theory. There are contributions of the form m_q…

Nuclear Theory · Physics 2009-11-07 Jiunn-Wei Chen , Martin J. Savage

The rate of mixing between a neutral kaon and an anti-kaon ($K^0-\bar{K}^0$) is given, in part, by a long-range matrix element, defined with two insertions of the weak Hamiltonian separated by physical, Minkowski time evolution. For…

High Energy Physics - Lattice · Physics 2022-12-21 Andrew W. Jackura , Raúl A. Briceńo , Maxwell T. Hansen

We compute the electromagnetic form factors of the proton and neutron using lattice QCD with $N_f = 2 + 1 + 1$ twisted mass clover-improved fermions and quark masses tuned to their physical values. Three ensembles with lattice spacings of…

High Energy Physics - Lattice · Physics 2025-02-18 Constantia Alexandrou , Simone Bacchio , Giannis Koutsou , Bhavna Prasad , Gregoris Spanoudes

We present results on the Omega baryon electromagnetic form factors using N_f= 2 + 1 dynamical domain-wall fermion configurations corresponding to a pion mass of about 330 MeV. We construct appropriate sequential sources for the…

High Energy Physics - Lattice · Physics 2010-11-05 C. Alexandrou , T. Korzec , G. Koutsou , Y. Proestos

We apply a formalism inspired by heavy baryon chiral perturbation theory with finite-range regularization to dynamical $2+1-$flavor CSSM/QCDSF/UKQCD Collaboration lattice QCD simulation results for the electric form factors of the octet…

High Energy Physics - Lattice · Physics 2017-01-10 P. E. Shanahan , A. W. Thomas , R. D. Young , J. M. Zanotti , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

We report on our calculation of pion and kaon form factors in three-flavor QCD using the overlap quark action. Gauge ensembles are generated on a 16^3 \times 48 lattice at a lattice spacing of 0.11 fm with pion masses down to 310 MeV.…

High Energy Physics - Lattice · Physics 2010-12-02 JLQCD Collaboration , T. Kaneko , S. Aoki , G. Cossu , H. Fukaya , S. Hashimoto , J. Noaki , T. Onogi

We perform for the first time a direct calculation of on-shell $K\to\pi\pi$ hadronic matrix elements of chromomagnetic operators (CMO) in the Standard Model and beyond. To his end, we use the successful Dual QCD (DQCD) approach in which we…

High Energy Physics - Phenomenology · Physics 2018-08-15 Andrzej Buras , Jean-Marc Gerard

Using Nf=2+1+1 lattice QCD, we determine the fermionic connected contributions to the second and third moment of the pion PDF. Based on gauge configurations from the European Twisted Mass Collaboration, chiral and continuum extrapolations…

High Energy Physics - Lattice · Physics 2021-02-22 M. Oehm , C. Alexandrou , M. Constantinou , K. Jansen , G. Koutsou , B. Kostrzewa , F. Steffens , C. Urbach , S. Zafeiropoulos