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Related papers: Medium Modification of the Proton Form Factor

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The recoil proton polarization has been measured in the p (\vec e,e'\vec p) pi^0 reaction in parallel kinematics around W = 1232 MeV, Q^2 = 0.121 (GeV/c)^2 and epsilon = 0.718 using the polarized c.w. electron beam of the Mainz Microtron.…

The electric form factor of the neutron, G_En, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(e_pol,e'n_pol)p reaction. Three data points have been extracted at squared four-momentum transfers Q^2 =…

The proton elastic form factor ratio can be measured either via Rosenbluth separation in an unpolarized beam and target experiment, or via the use of polarization degrees of freedom. However, data produced by these two approaches show a…

Nuclear Experiment · Physics 2018-06-13 Jan C. Bernauer

Recent polarization transfer measurements of the proton form factors disagree with previous Rosenbluth extractions. In addition to providing insight into the proton structure, the form factors also provide crucial input for the analysis of…

Nuclear Experiment · Physics 2019-08-14 J. Arrington

The proton elastic form factor ratio can be measured either via Rosenbluth separation in an experiment with unpolarized beam and target, or via the use of polarization degrees of freedom. However, data produced by these two approaches show…

Nuclear Experiment · Physics 2021-11-03 Ethan Cline , Jan C. Bernauer , Axel Schmidt

The beam-recoil double polarization P_{x'}^h and P_{z'}^h and the recoil polarization P_{y'} were measured for the first time for the p(\vec{e},e'\vec{p})\eta reaction at a four-momentum transfer of Q^2=0.1 GeV^2/c^2 and a center of mass…

Elastic form factors provide information about the low energy structure of composite particles.Recent double polarization coincidence experiments significantly improved our knowledge of proton and neutron form factors. Recoil polarization…

Nuclear Experiment · Physics 2007-05-23 H. Schmieden

The GEp-III and GEp-2$\gamma$ experiments were carried out in Jefferson Lab's (JLab's) Hall C from 2007-2008, to extend the knowledge of $G_E^p/G_M^p$ to the highest practically achievable $Q^2$ and to search for effects beyond the Born…

Measurements of the transverse polarization coefficient Kyy' for the reaction 3H(p,n)3He are reported for outgoing neutron energies of 1.94, 5.21, and 5.81 MeV. This reaction is important both as a source of polarized neutrons for nuclear…

Nuclear Experiment · Physics 2009-10-30 W. S. Wilburn , C. R. Gould , G. M. Hale , P. R. Huffman , C. D. Keith , N. R. Roberson , W. Tornow

We report new measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, GEn/GMn, obtained via recoil polarimetry from the quasielastic ^2H(vec{e},e'vec{n})^1H reaction at Q^2 values of 0.45, 1.13, and…

Nuclear Experiment · Physics 2012-08-27 038 Collaboration , R. Madey , A. Yu. Semenov , S. Taylor , B. Plaster

We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic range. The kinetic energy distribution for `fast' nucleons (p > 250 MeV/c) peaks where two nucleons each have 20% or less, and the third nucleon has most of the…

Nuclear Experiment · Physics 2010-04-06 CLAS Collaboration , R. A. Niyazov , L. B. Weinstein

Transverse momentum ($p_{\rm{T}}$) spectra of pions, kaons, and protons up to $p_{\rm{T}} = 20$ GeV/$c$ have been measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV using the ALICE detector for six different centrality classes…

Nuclear Experiment · Physics 2016-04-12 ALICE Collaboration

The recently published final results of experiment E04-108 in Jefferson Lab Hall C extend the recoil polarization measurements of the ratio of the proton electric and magnetic form factors to $Q^2 = 8.5$ GeV$^2$, an increase in $Q^2$…

Nuclear Experiment · Physics 2019-08-21 A. J. R. Puckett

The ratio of the proton's elastic electromagnetic form factors was obtained by measuring the transverse and longitudinal polarizations of recoiling protons from the elastic scattering of polarized electrons with unpolarized protons. The…

Nuclear Experiment · Physics 2008-11-26 The Jefferson Lab Hall A Collaboration , M. K. Jones

We measured the high-momentum quasi-elastic 12C(p,2p) reaction (at center of mass angle near 90 degrees) for 6 and 7.5 GeV/c incident protons. The three-momentum components of both final state protons were measured and the missing energy…

We estimate two-photon exchange contribution to the process $e^+ +e^- \to p + \bar{p}$. The two-photon exchange corrections to double spin polarization observables and form factors in the time-like region are calculated. The corrections are…

Nuclear Theory · Physics 2008-11-26 D. Y. Chen , H. Q. Zhou , Y. B. Dong

We update our previous studies of nuclear-matter effects on J/Psi production in proton-nucleus for the recent LHC pPb runs at sqrt(s_NN)=5 TeV. We have analysed the effects of the modification of the gluon PDFs in nucleus, using an exact…

High Energy Physics - Phenomenology · Physics 2013-10-14 E. G. Ferreiro , F. Fleuret , J. P. Lansberg , A. Rakotozafindrabe

Measurements of proton structure functions made in neutral and charged current interactions at HERA are discussed, covering four-momentum transfers Q^2 from about 0.5 GeV^2 to 30000 GeV^2. The results include the rise of the structure…

High Energy Physics - Experiment · Physics 2017-08-23 Joerg Gayler

Proton-${}^3$H elastic scattering and charge-exchange reaction ${}^3$H$(p,n){}^3$He in the energy regime above four-nucleon breakup threshold are described in the momentum-space transition operator framework. Fully converged results are…

Nuclear Theory · Physics 2017-06-05 A. Deltuva , A. C. Fonseca

The measurement of the 2P^{F=2}_{3/2} to 2S^{F=1}_{1/2} transition in muonic hydrogen by Pohl et al. and subsequent analysis has led to the conclusion that the rms radius of the proton differs from the accepted (CODATA) value by…

Atomic Physics · Physics 2011-08-15 J. D. Carroll , A. W. Thomas , J. Rafelski , G. A. Miller