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We present a lattice calculation of the electromagnetic (EM) effects on the masses of light pseudoscalar mesons. The simulations employ 2+1 dynamical flavors of asqtad QCD quarks, and quenched photons. Lattice spacings vary from $\approx…

Method of calculating hadron multi-point functions and disconnected quark loop contributions which are not readily accessible through conventional techniques is proposed. Results are reported for pion-pion, pion-nucleon and nucleon-nucleon…

High Energy Physics - Lattice · Physics 2009-10-22 Y. Kuramashi , M. Fukugita , H. Mino , M. Okawa , A. Ukawa

In this document, we summarize the status and challenges of calculating parton physics in lattice QCD for the US Particle Physics Community Planning Exercise (a.k.a. "Snowmass"). While PDF-moments calculations have been very successful and…

We present an exploratory study of leading isospin breaking effects in mesonic masses using $O(a)$ improved Wilson fermions. Isospin symmetry is explicitly broken by distinct masses and electric charges of the up and down quarks. In order…

High Energy Physics - Lattice · Physics 2018-04-18 Andreas Risch , Hartmut Wittig

The status of lattice calculations for heavy quark systems is reviewed, focussing on weak matrix elements for leptonic and semi-leptonic decays of heavy mesons. After an assessment of the main systematic errors, results for the decay…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hartmut Wittig

A method for computing electromagnetic properties of hadrons in lattice QCD is described. The electromagnetic field is introduced dynamically, using a noncompact formulation. Employing enhanced electric charges, the dependence of the…

High Energy Physics - Lattice · Physics 2009-10-28 A. Duncan , E. Eichten , H. Thacker

The different ground state energies of N-pion and M-kaon systems for N+M <=12 are studied in lattice QCD. These energies are then used to extract the various two- and three- body interactions that occur in these systems. Particular…

High Energy Physics - Lattice · Physics 2011-08-11 William Detmold , Brian Smigielski

We report on the physical-point RBC/UKQCD calculation of the leading isospin-breaking corrections to light-meson leptonic decays. This is highly relevant for future precision tests in the flavour physics sector, in particular the first-row…

We describe an independent method for determining the strong-isospin breaking mass parameter, 2delta = m_d - m_u, which utilizes the baryon spectrum. We use a prudent partially quenched choice of splitting the valence quark masses…

High Energy Physics - Lattice · Physics 2010-11-18 Andre Walker-Loud

In a previous letter (arXiv:1306.2287) we determined the isospin mass splittings of the baryon octet from a lattice calculation based on quenched QED and $N_f{=}2{+}1$ QCD simulations with 5 lattice spacings down to $0.054~\mathrm{fm}$,…

High Energy Physics - Lattice · Physics 2016-08-24 Z. Fodor , C. Hoelbling , S. Krieg , L. Lellouch , Th. Lippert , A. Portelli , A. Sastre , K. K. Szabo , L. Varnhorst

The leading-order electromagnetic and strong isospin-breaking corrections to the ratio of $K_{\mu 2}$ and $\pi_{\mu 2}$ decay rates are evaluated for the first time on the lattice, following a method recently proposed. The lattice results…

High Energy Physics - Lattice · Physics 2018-02-21 D. Giusti , V. Lubicz , G. Martinelli , C. T. Sachrajda , F. Sanfilippo , S. Simula , N. Tantalo , C. Tarantino

We report on our exploratory study for the direct evaluation of the parton distribution functions from lattice QCD, based on a recently proposed new approach. We present encouraging results using Nf = 2 + 1 + 1 twisted mass fermions with a…

We construct several classes of hadronic matrix elements and relate them to the low-energy constants in Chiral Perturbation Theory that describe the electromagnetic effects in the semileptonic beta decay of the pion and the kaon. We propose…

High Energy Physics - Lattice · Physics 2020-10-29 Chien-Yeah Seng , Xu Feng , Mikhail Gorchtein , Lu-Chang Jin , Ulf-G. Meißner

We report a first, complete lattice QCD calculation of the long-distance contribution to the $K^+\to\pi^+\nu\bar{\nu}$ decay within the standard model. This is a second-order weak process involving two four-Fermi operators that is highly…

High Energy Physics - Lattice · Physics 2017-06-28 Ziyuan Bai , Norman H. Christ , Xu Feng , Andrew Lawson , Antonin Portelli , Christopher T. Sachrajda

QCD sum rules using polynomial kernels are used to evaluate the strong part of the proton-neutron mass difference DeltaM_np in a model independent fashion. The result for the mass difference turns out to depend sensitively on the value of…

High Energy Physics - Phenomenology · Physics 2015-06-05 Nasrallah F. Nasrallah

We present results of a perturbative QCD analysis of deep inelastic measurements of both the deuteron and proton structure functions. We evaluate the theoretical uncertainty associated to nuclear effects in the deuteron, and we extract…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. I. Alekhin , S. A. Kulagin , S. Liuti

Numerical evaluation of the path integral for QCD on a discrete space-time lattice has been used to calculate ground state matrix elements specifying moments of quark density and spin distributions. This talk will explain how these matrix…

High Energy Physics - Lattice · Physics 2008-11-26 J. W. Negele

In this contribution we present a lattice calculation of the leading-order electromagnetic and strong isospin-breaking (IB) corrections to the quark-connected hadronic-vacuum-polarization (HVP) contribution to the anomalous magnetic moment…

High Energy Physics - Lattice · Physics 2019-09-05 Davide Giusti , Vittorio Lubicz , Guido Martinelli , Francesco Sanfilippo , Silvano Simula

Since the numerical path integration in the lattice QCD involves quark and gluon fields (not hadron fields) the lattice QCD cannot calculate any hadronic observable. Because of this reason the hadronic properties are extracted in the…

High Energy Physics - Lattice · Physics 2018-07-18 Gouranga C Nayak

We use the infinite volume reconstruction method to calculate the charged/neutral pion mass difference. The hadronic tensor is calculated on lattice QCD and then combined with an analytic photon propagator, and the mass splitting is…

High Energy Physics - Lattice · Physics 2022-02-23 Xu Feng , Luchang Jin , Michael Joseph Riberdy