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Related papers: The Proton Radius Puzzle

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We show that in previous analyses of electron-proton scattering, the uncertainties in the statistical procedure to extract the proton charge radius are underestimated. Using a fit function based on a conformal mapping, we can describe the…

High Energy Physics - Phenomenology · Physics 2014-08-28 I. T. Lorenz , U. -G. Meißner

The methods of Bayesian statistics are used to extract the value of the proton radius from the elastic $ep$ scattering data in a model independent way. To achieve that goal a large number of parametrizations (equivalent to neural network…

High Energy Physics - Phenomenology · Physics 2015-05-15 Krzysztof M. Graczyk , Cezary Juszczak

In this paper, we apply the Maximum Entropy Method to estimate the proton radius and determine the valence quark distributions in the proton at extremely low resolution scale Q$^{2}_{0}$. Using the simplest functional form of the valence…

High Energy Physics - Phenomenology · Physics 2017-09-04 Chengdong Han , Xurong Chen

Recently the muonic hydrogen lamb shift has been measured with unprecedented accuracy, allowing for a precise determination of the proton radius. This determination is 5 sigma away from the previous CODATA value obtained from (mainly) the…

High Energy Physics - Phenomenology · Physics 2011-08-08 Antonio Pineda

Recently there has been disagreement between various experiments about the value of the proton radius which is known as the proton radius puzzle. Since the proton is not a point particle the charge radius of the proton depends on the charge…

General Physics · Physics 2019-08-06 Gouranga C Nayak

We present a dispersion theoretical analysis of recent date from electron-proton scattering. This allows for a high-precision extraction of the electric and magnetic radius of the proton, $r_E = (0.839\pm 0.002{}^{+0.002}_{-0.003})$~fm and…

High Energy Physics - Phenomenology · Physics 2022-02-18 Yong-Hui Lin

The "proton size puzzle" and the "muon anomalous moment problem" are incomplete descriptions of significant discrepancies of Standard Model calculations with experiments. What is particularly new is that the experiments and theory confront…

High Energy Physics - Phenomenology · Physics 2016-06-21 John Craig Martens , John P. Ralston

A measurement of the Lamb shift in muonic hydrogen yields a charge radius of the proton that is smaller than the CODATA value by about 5 standard deviations. We explore the possibility that new scalar, pseudoscalar, vector, and tensor…

High Energy Physics - Phenomenology · Physics 2011-04-12 Vernon Barger , Cheng-Wei Chiang , Wai-Yee Keung , Danny Marfatia

The recent conundrum with the proton charge radius inspires reconsideration of the corrections that enter into determinations of the proton size. We study the two-photon proton-structure corrections, with special consideration of the…

High Energy Physics - Phenomenology · Physics 2013-05-29 Carl E. Carlson , Marc Vanderhaeghen

At present, neutron star radii from both observations and model predictions remain very uncertain. Whereas different models can predict a wide range of neutron star radii, it is not possible for most models to predict radii that are smaller…

Nuclear Theory · Physics 2015-09-25 Wei-Zhou Jiang , Bao-An Li , F. J. Fattoyev

Recent results on muonic hydrogen [1] and the ones compiled by CODATA on ordinary hydrogen and $ep$-scattering [2] are $5\sigma$ away from each other. Two reasons justify a further look at this subject: 1) One of the approximations used in…

High Energy Physics - Phenomenology · Physics 2015-03-17 A. De Rújula

The mass radius is a fundamental property of the proton that so far has not been determined from experiment. Here we show that the mass radius of the proton can be rigorously defined through the formfactor of the trace of the…

High Energy Physics - Phenomenology · Physics 2021-09-22 Dmitri E. Kharzeev

Reinforcement of the puzzle about the proton charge radius r, stimulated by the recent experiments with muonic hydrogen induced news discussions on the subject, and now some physicists are ready to adopt the exotic properties of muon, lying…

Atomic Physics · Physics 2015-06-16 Alexander L Kholmetskii , Oleg V Missevitch , Tolga Yarman

Charge radii of hadrons are back in the focus since precision spectroscopic measurements in muonic hydrogen revealed a proton charge radius considerably smaller than generally accepted ever since R.~Hofstaedter's pioneering experiments.…

High Energy Physics - Experiment · Physics 2023-11-02 Stephan Paul

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

Proton radii of $^{12-19}$C densities derived from first accurate charge changing cross section measurements at 900$A$ MeV with a carbon target are reported. A thick neutron surface evolves from $\sim$ 0.5 fm in $^{15}$C to $\sim$ 1 fm in…

High-precision laser spectroscopy of atomic energy levels enables the measurement of nuclear properties. Sensitivity to these properties is particularly enhanced in muonic atoms which are bound systems of a muon and a nucleus. Exemplary is…

Atomic Physics · Physics 2016-08-12 Aldo Antognini

To shed light on the deuteron radius puzzle we analyze the theoretical uncertainties of the nuclear structure corrections to the Lamb shift in muonic deuterium. We find that the discrepancy between the calculated two-photon exchange…

Nuclear Theory · Physics 2018-06-12 Oscar Javier Hernandez , Andreas Ekström , Nir Nevo Dinur , Chen Ji , Sonia Bacca , Nir Barnea

The deuteron charge radius is calculated from the measurement of the Lamb shift in muonic deuterium, taking into account the electron vacuum polarization correction to the nuclear-structure effects. This correction is unexpectedly large and…

Atomic Physics · Physics 2019-03-27 Marcin Kalinowski