Investigation of the conjectured nucleon deformation at low momentum transfer

Abstract

We report new precise H$(e,e^{\prime }p){\pi }^0$ measurements at the $\Delta (1232)$ resonance at $Q^2=0.127$ (GeV/c)${}^2$ using the MIT/Bates out-of-plane scattering (OOPS) facility. The data reported here are particularly sensitive to the transverse electric amplitude ($E2$) of the ${\gamma }^{\ast }N\to \Delta$ transition. Analyzed together with previous data yield precise quadrupole to dipole amplitude ratios $EMR=(-2.3\pm 0.3_{stat+sys}\pm 0.6_{model})$ and $CMR=(-6.1\pm 0.2_{stat+sys}\pm 0.5_{model})$ and for $M_{1+}^{3/2}=(41.4\pm 0.3_{stat+sys}\pm 0.4_{model})(10^{-3}/m_{{\pi }^{+}})$. They give credence to the conjecture of deformation in hadronic systems favoring, at low $Q^2$, the dominance of mesonic effects.

4 pages, 1figure

References in corpus (1)

• The N to Delta electromagnetic transition form factors from Lattice QCD

Cited by in corpus (80)

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• The N to Delta electromagnetic transition form factors from Lattice QCD
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• D-state effects in the electromagnetic N-Delta transition
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• Valence quark contribution for the gamma N -> Delta quadrupole transition extracted from lattice QCD
• Delta and Omega electromagnetic form factors in a Dyson-Schwinger/Bethe-Salpeter approach
• Signatures of chiral dynamics in the Nucleon to Delta transition
• Nucleon to Delta electromagnetic transition in the Dyson-Schwinger approach
• Extraction of Electromagnetic Transition Form Factors for Nucleon Resonances within a Dynamical Coupled-Channels Model
• Measurement of the LT-asymmetry in π^0 electroproduction at the energy of the Δ(1232) resonance
• Insights into the gamma* N -> Delta transition
• Hadron structure at low Q^2
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• Measurement of the neutron charge radius and the role of its constituents
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• Measurements of the gamma*p->Delta Reaction At Low Q^2: Probing the Mesonic Contribution
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• Recoil Polarization Measurements for Neutral Pion Electroproduction at Q^2=1 (GeV/c)^2 Near the Delta Resonance
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• $\Delta (1232)$ Resonance Contribution to Two-Photon Exchange in Electron-Proton Scattering Revisited
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• Electromagnetic Transition Form Factors of Baryon Resonances
• Nucleon resonance contributions to unpolarised inclusive electron scattering
• Transition form factors: ${\gamma }^{\ast }+p\to \Delta (1232)$, $\Delta (1600)$
• Dynamical Models of the Excitations of Nucleon Resonances
• Results from the N* program at JLab
• Neutral Pion Electroproduction in the Resonance Region at High $Q^2$
• Electromagnetic Nucleon-to-Delta Transition in Holographic QCD
• Nucleon resonances in Compton scattering
• Electromagnetic transition form factors of baryons in the space-like momentum region
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• Coupled-channel analysis of pion- and eta-electroproduction with the Jülich-Bonn-Washington model
• Study of nucleon resonances with electromagnetic interactions
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• Measurement of the Partial Cross Sections s(TT), s(LT) and [s(T)+epsilon*s(L)] of the p(e,e' pi+)n Reaction in the Delta(1232) Resonance
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