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Related papers: Proton radius puzzle and large extra dimensions

200 papers

The fact that the spins of the quarks in the proton, as measured in deep inelastic lepton scattering, only add up to about 30$\%$ of the spin of the proton is still not understood after 30 years. We show that our newly developed model for…

High Energy Physics - Phenomenology · Physics 2019-06-21 Andreas Ekstedt , Hazhar Ghaderi , Gunnar Ingelman , Stefan Leupold

The FAMU (Fisica degli Atomi Muonici) experiment at the RIKEN RAL pulsed muon facility will measure the proton Zemach radius with high precision, thus contributing to the solution of the so-called proton radius puzzle. The situation is now…

The radiative muon capture(RMC) on a proton is analyzed by means of heavy baryon chiral perturbation theory. The emitted photon energy spectrum is calculated and compared with the experimental data by taking the spin sum on the muonic atom…

High Energy Physics - Phenomenology · Physics 2009-10-30 Shung-ichi Ando , Dong-Pil Min

We demonstrate the potential of forthcoming mu -> e gamma and mu-e conversion experiments to implicate or disfavor solutions to the gauge hierarchy problem before the advent of the CERN Large Hadron Collider. Solutions of dynamical…

High Energy Physics - Phenomenology · Physics 2007-05-23 David W. Maybury , Brandon Murakami

This study explores the age-old quest to construct a geometric model of a quantum particle. While static classical particle models have largely been dismissed, the focus has now shifted to intricate dynamic models that hold the promise of…

General Relativity and Quantum Cosmology · Physics 2024-05-21 Michael Cramer Andersen

It is shown that in both the gluonic and strange sea explanations of the Ellis-Jaffe sum rule violation discovered by the European Muon Collaboration (EMC), the spin of the proton, when viewed in in its rest reference frame, could by fully…

High Energy Physics - Phenomenology · Physics 2009-10-22 Bo-Qiang Ma , Qi-Ren Zhang

The twenty years since the announcement of the proton spin crisis by the European Muon Collaboration has seen tremendous progress in our knowledge of the distribution of spin within the proton. The problem is reviewed, beginning with the…

High Energy Physics - Phenomenology · Physics 2010-11-11 A. W. Thomas , Jefferson Lab

Modified Newtonian Dynamics (MOND) is an alternative to the dark matter hypothesis that attempts to explain the "missing gravity" problem in astrophysics and cosmology through a modification to objects' dynamics. Since its conception in…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-29 Harry Desmond

A warped extra dimension model proposed by Randall and Sundrum(RS) is one of the attractive candidates to solve the gauge hierarchy problem in the Standard Model. In a simplest version of the RS model, there are only two extra particles…

High Energy Physics - Phenomenology · Physics 2014-03-03 Yoshiko Ohno

Understanding the spin structure of the proton is one of the main challenges in hadronic physics. While the concepts of spin and orbital angular momentum are pretty clear in the context of non-relativistic quantum mechanics, the…

High Energy Physics - Phenomenology · Physics 2015-04-21 Cédric Lorcé

The uncertainty in the contribution to the Lamb shift in muonic hydrogen, $\Delta E^{subt}$ arising from proton polarizability effects in the two-photon exchange diagram at large virtual photon momenta is shown large enough to account for…

Nuclear Theory · Physics 2015-06-11 Gerald A. Miller

The proton is one of the main building blocks of all visible matter in the universe. Among its intrinsic properties are its electric charge, mass, and spin. These emerge from the complex dynamics of its fundamental constituents, quarks and…

The neutron radius of a heavy nucleus is a fundamental nuclear-structure observable that remains elusive. Progress in this arena has been limited by the exclusive use of hadronic probes that are hindered by large and controversial…

Nuclear Theory · Physics 2008-11-26 J. Piekarewicz

The contribution of virtual excitations to the energy levels of electronic and muonic hydrogen is investigated combining a model-independent approach for the main part with quark model predictions for the remaining corrections. Precise…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Rosenfelder

In the paper Int.J.Mod.Phys.E 23 (2014) 1450004, the potential of short-baseline experiments was proposed to measure the mass (and parameters of Lorentz-violating effects) of the muon neutrino, where a roughly estimated upper bound of 420…

High Energy Physics - Phenomenology · Physics 2024-05-03 A. M. Attia , I. G. Márián , B. Ujvári

A unified set of predictions for pion and kaon elastic electromagnetic and gravitational form factors is obtained using a symmetry-preserving truncation of each relevant quantum field equation. A key part of the study is a description of…

High Energy Physics - Phenomenology · Physics 2023-11-28 Yin-Zhen Xu , Minghui Ding , Khépani Raya , Craig D. Roberts , José Rodríguez-Quintero , Sebastian M. Schmidt

The finding of Gravitational Waves by the aLIGO scientific and VIRGO collaborations opens opportunities to better test and understand strong interactions, both nuclear-hadronic and gravitational. Assuming General Relativity holds, one can…

Nuclear Theory · Physics 2017-04-05 Felipe J. Llanes-Estrada

Decoding the internal structure of the proton is a fundamental challenge in physics. Historically, any new discovery about the proton has fuelled advances in several scientific fields. We have reported that gluons inside the proton…

High Energy Physics - Phenomenology · Physics 2025-10-08 Wei Zhu , Jianhong Ruan , Xurong Chen , Yuchen Tang

In this paper we investigate the link between classical electrodynamics and the mass-energy equivalence principle, in view of the conclusions reached in ref.[1]. A formula for the radius of a charged particle is derived. The formula…

General Physics · Physics 2009-07-16 Ezzat G. Bakhoum

The Lamb shift in muonic hydrogen was measured some time ago to a high accuracy. The theoretical prediction of this value is very sensitive to the proton-finite-size effects. The proton radius extracted from muonic hydrogen is in…

High Energy Physics - Phenomenology · Physics 2015-04-16 Savely G. Karshenboim , Evgeny Yu. Korzinin , Vladimir G. Ivanov , Valery A. Shelyuto