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Related papers: Lattice QCD Method To Study Proton Radius Puzzle

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Constraints from analyticity are combined with experimental electron-proton scattering data to determine the proton charge radius. In contrast to previous determinations, we provide a systematic procedure for analyzing arbitrary data…

High Energy Physics - Phenomenology · Physics 2010-12-24 Richard J. Hill , Gil Paz

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

It is suggested that proton elastic scattering on atomic electrons allows a precise measurement of the proton charge radius. Very small values of transferred momenta (up to four order of magnitude smaller than the ones presently available)…

Nuclear Theory · Physics 2015-06-03 G. I. Gakh , A. Dbeyssi , E. Tomasi-Gustafsson , D. Marchand , V. V. Bytev

Momentum and spatial distributions of quarks and gluons inside hadrons are typically encoded in the so-called generalized parton distributions (GPDs). GPDs are multi-dimensional quantities that are very challenging to extract, both…

Recent progress in hadron structure calculations within lattice QCD is reviewed. Results on key observables such as the axial charge, the quark momentum fraction and the spin content of the nucleon are discussed with focus on open issues.…

High Energy Physics - Lattice · Physics 2015-06-03 Constantia Alexandrou

We comment on the status and history of the proton charge radius determinations.

High Energy Physics - Phenomenology · Physics 2020-01-22 Hans-Werner Hammer , Ulf-G. Meißner

A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods applied for…

High Energy Physics - Lattice · Physics 2022-03-02 C. Alexandrou , M. Constantinou , V. Drach , K. Hatziyiannakou , K. Jansen , C. Kallidonis , G. Koutsou , T. Leontiou , A. Vaquero

Parton distribution functions are key quantities for us to understand the hadronic structures in high-energy scattering, but they are difficult to calculate from lattice QCD. Recent years have seen fast development of the large-momentum…

High Energy Physics - Phenomenology · Physics 2019-04-29 Yong Zhao

We present preliminary results on the proton spin structure function in full QCD. The measurement has been done using 4 flavours of staggered fermions and an improved definition of the lattice topological charge density.

High Energy Physics - Lattice · Physics 2009-09-25 B. Alles , G. Boyd , M. D'Elia , A. Di Giacomo

The proton radius puzzle remains a key challenge in modern physics, highlighting both the precision and limitations of current experimental and theoretical approaches. Recent studies, such as those by Xiong et al. and Bezginov et al., have…

Nuclear Experiment · Physics 2025-01-22 Roland B. Lumpay , Jade C. Jusoy , Ruel Apas , Eulogio Auxtero

Following previous works on that topic, we consider Euclidean hadronic matrix elements in position space of two spatially separated local currents on the lattice, in order to extract the $x$ dependence of parton distribution functions…

High Energy Physics - Lattice · Physics 2024-10-11 Christian Zimmermann , Andreas Schäfer

We have analyzed the proton form factor data by using a number of phenomenological parameterizations (models) and extracting the proton electric and magnetic radii. To this end we performed a global fit to all available form factor data,…

High Energy Physics - Phenomenology · Physics 2024-01-12 M. Ridwan , T. Mart

We formulate lattice QCD in rotating frames to study the physics of QCD matter under rotation. We construct the lattice QCD action with the rotational metric and apply it to the Monte Carlo simulation. As the first application, we calculate…

High Energy Physics - Lattice · Physics 2013-08-23 Arata Yamamoto , Yuji Hirono

We present a lattice QCD calculation of the unpolarized isovector quark parton distribution function (PDF) of the proton utilizing a perturbative matching at next-to-next-to-leading-order (NNLO). The calculations are carried out using a…

High Energy Physics - Lattice · Physics 2023-05-10 Xiang Gao , Andrew D. Hanlon , Jack Holligan , Nikhil Karthik , Swagato Mukherjee , Peter Petreczky , Sergey Syritsyn , Yong Zhao

A new calculation of the neutron electric form factor is described. Preliminary results for the connected part on a $20^{3}\times 32$ lattice are presented. The methods for calculating the disconnected part are briefly described.

High Energy Physics - Lattice · Physics 2007-05-23 Walter Wilcox

We calculate the form factor of the quark energy momentum tensor and thereby extract the quark orbital angular momentum of the nucleon. The calculation is done on a quenched $16^3 \times 24$ lattice at $\beta = 6.0$ and with Wilson fermions…

High Energy Physics - Lattice · Physics 2015-06-25 Nilmani Mathur , S. J. Dong , K. F. Liu , N. C. Mukhopadhyay

We present a new method to evaluate with high precision the isospin breaking effects due to the mass difference between the up and down quarks using lattice QCD. Our proposal is applicable in principle to any hadronic observable which can…

Parton distribution functions give the probability to find partons (quarks and gluons) in a hadron as a function of the fraction x of the proton's momentum carried by the parton. They are conventionally defined in terms of matrix elements…

High Energy Physics - Lattice · Physics 2009-10-28 Davison E. Soper

We review the current status of lattice QCD studies of the nucleon system. In particular, we focus on the determination of the shape of the nucleon by probing its wave function as well as by evaluating the N to Delta transition form…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou

We present an analysis of the proton mass radius by studying the $t$-dependence of the differential cross sections of the vector meson photoproductions near the thresholds. At low energy, the photoproduction of a quarkonium off the proton…

High Energy Physics - Phenomenology · Physics 2021-05-19 Rong Wang , Wei Kou , Ya-Ping Xie , Xurong Chen