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Zhan, X.; Allada, K.; Armstrong, David; Arrington, J.; Bertozzi, W.; Boeglin, W.; Chen, J.-P.; Chirapatpimol, K.; Choi, S.; Chudakov, E.; Cisbani, E.; Decowski, P.; Dutta, C.; Frullani, S.; Fuchey, E.; Garibaldi, F.; Gilad, S.; Gilman, R.; Glister, J.; Hafidi, K.; Hahn, B.; Hansen, J. O.; Higinbotham, D. W.; Holmstrom, T.; Holt, R. J.; Huang, J.; Huber, G. M.; Itard, F.; Jager, C. W. de; Jiang, X.; Johnson, M. A.; Katich, Joseph M.; Лео, Р. Де; LeRose, J.; Lindgren, R.; Long, E.; Margaziotis, D. J.; Beck, S. May-Tal; Meekins, D.; Michaels, R.; Moffit, B.; Norum, B.; Olson, M.; Piasetzky, E.; Pomerantz, I.; Protopopescu, D.; Qian, X.; Qiang, Y.; Rakhman, A.; Ransome, R. D.; Reimer, P. E.; Reinhold, J.; Riordan, S.; Ron, G.; Saha, A.; Sarty, A. J.; Sawatzky, B.; Schulte, E.; Shabestari, M.; Shahinyan, A.; Shneor, R.; Širca, S.; Solvignon, P.; Sparveris, N.; Strauch, S.; Subedi, R.; Sulkosky, V.; Vilardi, I.; Wang, Y.; Wojtsekhowski, B.; Ye, Z.; Zhang, Y.

doi:10.1016/j.physletb.2011.10.002

Cited by 183 publications

(101 citation statements)

References 39 publications

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“…Our error bars are larger than these extraction, which is not unusual when using model-independent methods [76,94]. Other extractions of the proton magnetic radius from scattering data that were not quoted by the PDG are r p M = 0.855 ± 0.035 fm [111], r p M = 0.867 ± 0.020 fm [112], and r p M = 0.86 +0.02 −0.03 fm [113]. Our results are consistent with theses values too.…”

Section: Discussionsupporting

confidence: 46%

Model independent extraction of the proton magnetic radius from electron scattering

2014

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We combine constraints from analyticity with experimental electron-proton scattering data to determine the proton magnetic radius without model-dependent assumptions on the shape of the form factor. We also study the impact of including electron-neutron scattering data, and ππ → NN data. Using representative datasets we find for a cut of Q 2 ≤ 0.5 GeV 2 , r p M = 0.91 +0.03 −0.06 ± 0.02 fm using just proton scattering data; r p M = 0.87 +0.04 −0.05 ± 0.01 fm adding neutron data; and r p M = 0.87 +0.02 −0.02 fm adding ππ data. We also extract the neutron magnetic radius from these data sets obtaining r n M = 0.89 +0.03 −0.03 fm from the combined proton, neutron, and ππ data.

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Section: Discussionsupporting

confidence: 46%

Model independent extraction of the proton magnetic radius from electron scattering

2014

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“…[73]. The origin of the sizeable discrepancy between the two experimental results for the proton magnetic radius is discussed, for example, in Ref.…”

Section: Nucleon Form Factor Resultsmentioning

confidence: 99%

Role of diquark correlations and the pion cloud in nucleon elastic form factors

2014

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Electromagnetic form factors of the nucleon in the space-like region are investigated within the framework of a covariant and confining Nambu-Jona-Lasinio model. The bound state amplitude of the nucleon is obtained as the solution of a relativistic Faddeev equation, where diquark correlations appear naturally as a consequence of the strong coupling in the colour3 qq channel. Pion degrees of freedom are included as a perturbation to the "quark-core" contribution obtained using the Poincaré covariant Faddeev amplitude. While no model parameters are fit to form factor data, excellent agreement is obtained with the empirical nucleon form factors (including the magnetic moments and radii) where pion loop corrections play a critical role for Q 2 1 GeV 2 . Using charge symmetry, the nucleon form factors can be expressed as proton quark sector form factors. The latter are studied in detail, leading, for example, to the conclusion that the d-quark sector of the Dirac form factor is much softer than the u-quark sector, a consequence of the dominance of scalar diquark correlations in the proton wave function. On the other hand, for the proton quark sector Pauli form factors we find that the effect of the pion cloud and axialvector diquark correlations overcomes the effect of scalar diquark dominance, leading to a larger d-quark anomalous magnetic moment and a form factor in the u-quark sector that is slightly softer than in the d-quark sector.

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“…The eH value is backed up by the extractions from electronproton (ep) scattering [5,6], albeit with a notable exception [7]. The next-to-leading order (NLO) effect of the nuclear charge distribution is given by [8]:…”

Section: Introductionmentioning

confidence: 99%

Breakdown of the expansion of finite-size corrections to the hydrogen Lamb shift in moments of charge distribution

Hagelstein

Pascalutsa

2015

Phys. Rev. A

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We quantify a limitation in the usual accounting of the finite-size effects, where the leading [(Zα) 4 ] and subleading [(Zα) 5 ] contributions to the Lamb shift are given by the mean-square radius and the third Zemach moment of the charge distribution. In the presence of any non-smooth behaviour of the nuclear form factor at scales comparable to the inverse Bohr radius, the expansion of the Lamb shift in the moments breaks down. This is relevant for some of the explanations of the "proton size puzzle". We find, for instance, that the de Rújula toy model of the proton form factor does not resolve the puzzle as claimed, despite the large value of the third Zemach moment. Without relying on the radii expansion, we show how tiny, milli-percent (pcm) changes in the proton electric form factor at a MeV scale would be able to explain the puzzle. It shows that one needs to know all the soft contributions to proton electric form factor to pcm accuracy for a precision extraction of the proton charge radius from atomic Lamb shifts.

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High-precision measurement of the proton elastic form factor ratio μpGE/GM at low Q

Cited by 183 publications

References 39 publications

Model independent extraction of the proton magnetic radius from electron scattering

Model independent extraction of the proton magnetic radius from electron scattering

Role of diquark correlations and the pion cloud in nucleon elastic form factors

Breakdown of the expansion of finite-size corrections to the hydrogen Lamb shift in moments of charge distribution

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