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Related papers: Medium Modification of the Proton Form Factor

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Cross sections for the 3He(e,e'pp)n reaction were measured over a wide range of energy and three- momentum transfer. At a momentum transfer q=375 MeV/c, data were taken at transferred energies omega ranging from 170 to 290 MeV. At omega=220…

The p(p,e^+ \nu_e)^2H reaction rate is an essential ingredient for theoretical computations of stellar models. In the past several values of the corresponding S-factor have been made available by different authors. Prompted by a recent…

Solar and Stellar Astrophysics · Physics 2015-06-23 E. Tognelli , S. Degl'Innocenti , L. E. Marcucci , P. G. Prada Moroni

The electromagnetic inclusive responses of polarized $^{3}$He and $^{3}$H are thoroughly investigated at the quasielastic peak for squared momentum transfers up to $2 (GeV/c)^2$, within the plane wave impulse approximation. Great emphasys…

Nuclear Theory · Physics 2008-11-26 A. Kievsky , E. Pace , G. Salme` , M. Viviani

Recent recoil polarization measurements in Hall A at Jefferson Lab show that the ratio of the electric to magnetic form factors for the proton decreases significantly with increasing Q^2. This contradicts previous Rosenbluth measurements…

Nuclear Experiment · Physics 2017-08-23 J. Arrington

We report a new determination of the strange quark contribution to the proton's magnetic form factor at a four-momentum transfer Q2 = 0.1 (GeV/c)^2 from parity-violating e-p elastic scattering. The result uses a revised analysis of data…

Nuclear Experiment · Physics 2009-07-09 SAMPLE collaboration , D. T. Spayde

The momentum distribution of the electron in the reaction p+He $\rightarrow$ H + He$^{2+}$ + $e$ is measured for projectile energies $E_p$=300 and 630 keV/u at very small scattering angles of hydrogen. We mainly present two dimensional…

One possible explanation for the proton form factor discrepancy is a contribution to the elastic electron-proton cross section from hard two-photon exchange (TPE), a typically neglected radiative correction. Hard TPE cannot be calculated in…

Nuclear Experiment · Physics 2020-04-08 Axel Schmidt

We extend to 10 GeV results from a microscopic calculation of charged-current neutrino-nucleus reactions that do not produce a pion in the final state. For the class of events coming from neutrino interactions with two nucleons producing…

High Energy Physics - Phenomenology · Physics 2014-02-17 R. Gran , J. Nieves , F. Sanchez , M. J. Vicente Vacas

Jet shape measurements are strongly suggested to explore the microscopic evolution mechanism of parton-medium interaction in ultra-relativistic heavy-ion collisions. In this paper, jet shape modifications are quantified by fragmentation…

High Energy Physics - Phenomenology · Physics 2019-05-22 Renzhuo Wan , Lei Ding , Xi Gui , Fan Yang , Shuang Li , Daicui Zhou

A measurement of the proton structure function $F_{\!2}(x,Q^2)$ is reported for momentum transfer squared $Q^2$ between 4.5 $GeV^2$ and 1600 $GeV^2$ and for Bjorken $x$ between $1.8\cdot10^{-4}$ and 0.13 using data collected by the HERA…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

The effect of meson and isobar degrees of freedom in A($\vec{e},e'\vec{p}$) and A(e,e'n) is studied for four-momentum transfers Q^2 in the range between 0.2 and 0.8 (GeV/c)^2. The calculations are performed in a non-relativistic framework…

Nuclear Theory · Physics 2016-09-08 Jan Ryckebusch , Dimitri Debruyne , Wim Van Nespen , Stijn Janssen

Existing cross-section data for 1p-shell knockout in the reaction 12C(e,e'p) - as obtained under different kinematic conditions - are shown to be mutually consistent, apart from a recent measurement performed in Mainz. New data have been…

Nuclear Experiment · Physics 2010-12-15 L. Lapikas , G. van der Steenhoven , L. Frankfurt , M. Strikman , M. Zhalov

We discuss questions related to the interpretation of unexpected results of measurements of the proton form factors ratio G_E/G_M in the polarization experiments done in JLab in the region of 0.5 < Q^2 < 8.5 GeV^2. For this purpose, in the…

Nuclear Theory · Physics 2013-02-05 M. V. Galynskii , E. A. Kuraev

A criterion for assessing the reliability of measurements of the Sachs form factor ratio using the Rosenbluth technique is proposed and applied to an analysis of three known experiments (Andivahis1994, Walker1994, Qattan2005) and a recent…

Nuclear Experiment · Physics 2022-03-02 M. V. Galynskii

We estimate the two-photon exchange corrections to both proton and neutron electromagnetic physical observables in a relativistic light cone quark model. At a fixed momentum transfer the corrections are found to be small in magnitudes, but…

Nuclear Theory · Physics 2010-01-15 Dian-Yong Chen , Yu-Bing Dong

High precision measurements of the form factors of proton, pion, and kaon for timelike momentum transfers of |Q^2|=s=14.2 and 17.4 GeV^2 have been made. Data taken with the CLEO-c detector at sqrt(s)=3.772 GeV and 4.170 GeV, with integrated…

High Energy Physics - Experiment · Physics 2015-06-11 Kamal K. Seth , S. Dobbs , Z. Metreveli , A. Tomaradze , T. Xiao , G. Bonvicini

A proposal approved by the Jefferson Lab (JLab) PAC to study the proton-to-neutron momentum distribution ratio in A=3 nuclei via (e,e'p) scattering off 3He and 3H mirror nuclei. The experiment will measure the 3H(e,e'p) and 3He(e,e'p)…

Nuclear Experiment · Physics 2014-10-17 O. Hen , L. B. Weinstein , S. Gilad , W. Boeglin

The measurement by Pohl et al. [1] of the 2S_1/2^F=1 to 2P_3/2^F=2 transition in muonic hydrogen and the subsequent analysis has led to a conclusion that the rms charge radius of the proton differs from the accepted (CODATA [2]) value by…

Atomic Physics · Physics 2015-05-28 J. D. Carroll , A. W. Thomas , J. Rafelski , G. A. Miller

The electromagnetic structure of the baryons is modified in the nuclear medium. The modifications can be inferred from the comparison between the electromagnetic form factors in medium with the respective form factor in vacuum. Of…

High Energy Physics - Phenomenology · Physics 2021-10-28 G. Ramalho , K. Tsushima , J. P. B. C. de Melo

The reactions of electron-positron to nucleon-antinucleon pair at energy threshold are studied in a non-perturbative quark model. The puzzling experimental result that the ratio of the cross section of electron-positron to proton-antiproton…

High Energy Physics - Phenomenology · Physics 2009-07-03 Y. Yan , K. Khosonthongkee , C. Kobdaj , P. Suebka