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Related papers: Lattice QCD Method To Study Proton Radius Puzzle

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Recently a high-precision measurement of the Lamb shift in muonic hydrogen has been performed. An accurate value of the proton charge radius can be extracted from this datum with a high accuracy. To do that a sufficient accuracy should be…

High Energy Physics - Phenomenology · Physics 2014-11-04 Savely G. Karshenboim

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

We present the first calculation of the $x$-dependence of the isovector transversity generalized parton distributions (GPDs) for the proton within lattice QCD. We compute the matrix elements with non-local operators containing a Wilson…

The concept of nucleon radii plays a central role in our understanding of the internal structure of protons and neutrons, providing critical insights into the non-perturbative regime of quantum chromodynamics (QCD). While the charge radius…

High Energy Physics - Phenomenology · Physics 2025-05-21 The MMGPDs Collaboration , Muhammad Goharipour , Fatemeh Irani , M. H. Amiri , H. Fatehi , Behnam Falahi , A. Moradi , K. Azizi

We report our preliminary results for the charge radii of $\pi^{+}$ and $K^{+}$ mesons with the PACS10 configuration generated at the physical point using the Iwasaki gauge action and $N_{f}=2+1$ stout-smeared nonperturbatively…

High Energy Physics - Lattice · Physics 2024-12-25 Kohei Sato , Hiromasa Watanabe , Takeshi Yamazaki for PACS Collaboration

We report a state-of-the-art lattice QCD calculation of the isovector quark transversity distribution of the proton in the continuum and physical mass limit using large-momentum effective theory. The calculation is done at four lattice…

We present the current status of our lattice calculation of the electromagnetic form factor of the pion with two flavours of non-perturbatively O(a)-improved Wilson fermions. Using twisted boundary conditions and stochastic sources we…

High Energy Physics - Lattice · Physics 2013-01-17 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

A review of the calculations of the proton's spin using lattice QCD is presented. Results for the three contributions, the quark contribution $\sum_{q=u,d,s,c} (\frac{1}{2} {\Delta q})$, the total angular momentum of the quarks $J_q$ and of…

High Energy Physics - Lattice · Physics 2019-04-02 Rajan Gupta

We propose a fully non-perturbative method to compute inelastic lepton-nucleon ($\ell N$) scattering cross sections using lattice QCD. The method is applicable even at low energies, such as the energy region relevant for the recent and…

High Energy Physics - Lattice · Physics 2021-01-04 Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko , Hiroshi Ohki

Precision measurements on nucleons provide constraints on the Standard Model and can also discern the signatures predicted for particles beyond the Standard Model. Knowing the Standard Model inputs to nucleon matrix elements will be…

High Energy Physics - Lattice · Physics 2011-12-13 Huey-Wen Lin

In these proceedings, we summarize the main results from the first-ever calculations of the chiral-even and chiral-odd twist-3 parton distributions, $g_T(x)$ and $h_L(x)$, of the proton from lattice QCD. We use an $N_f=2+1+1$ ensemble of…

High Energy Physics - Lattice · Physics 2021-11-02 Shohini Bhattacharya , Krzysztof Cichy , Martha Constantinou , Andreas Metz , Aurora Scapellato , Fernanda Steffens

In a series of recent publications, different authors produce a wide range of electron radii when reanalyzing electron proton scattering data. In the light of the proton radius puzzle, this is a most unfortunate situation. However, we find…

Nuclear Theory · Physics 2016-06-08 Jan C. Bernauer , Michael O. Distler

The proton charge radius extracted from the recent muonic hydrogen spectroscopy [Antognini et al. 2013; Pohl et al. 2010] differs from the CODATA 2010 recommended value [Mohr et al. 2012] by more than 4% or $4.4 \sigma$. This discrepancy,…

High Energy Physics - Phenomenology · Physics 2013-03-22 Zhigang Li , Xuelei Chen

Theoretical predictions of the proton--neutron mass difference and measurements of the proton's charge radius require inputs from the Compton amplitude subtraction function. Model-dependent and non-relativistic calculations of this…

Understanding the internal structure of the proton-including the distributions of quarks and gluons and their contributions to proton properties such as mass-remains a central challenge in quantum chromodynamics (QCD). While quark…

High Energy Physics - Phenomenology · Physics 2026-03-06 Jiali Deng , Defu Hou

While QCD can provide corrections to the parton distribution function, it cannot produce the distribution. Where is then the starting point for the proton structure function? The only known source is the quark-model wave function for the…

High Energy Physics - Phenomenology · Physics 2014-08-19 Y. S. Kim

The nature of the proton wave function can be elucidated by studying the matrix elements of spin-dependent quark density operators SDDs, defined as matrix elements of density operators in proton states of definite spin-polarization. These…

Nuclear Theory · Physics 2011-08-31 Gerald A. Miller

At very high energy and wide angles, Compton scattering on the proton (gamma p -> gamma p) is described by perturbative QCD. The perturbative QCD calculation has been performed several times previously, at leading twist and at leading order…

High Energy Physics - Phenomenology · Physics 2009-05-01 Travis Brooks , Lance Dixon

The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative…

Nuclear Theory · Physics 2013-08-09 P. E. Shanahan , A. W. Thomas , K. Tsushima , R. D. Young , F. Myhrer

I review recent progress in the development of Lattice QCD into a calculational tool for nuclear physics. Lattice QCD is currently the only known way of solving QCD in the low-energy regime, and it promises to provide a solid foundation for…

Nuclear Theory · Physics 2015-05-30 Martin J. Savage