Neutral Pion Electroproduction in the Resonance Region at High $Q^2$

Abstract

The process $ep\to e^{\prime }{p}^{\prime }{\pi }^0$ has been measured at $Q^2$ = 6.4 and 7.7 GeV/c${}^2$)${}^2$ in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center of mass frame considering the process ${\gamma }^{\ast }p\to p^{\prime }{\pi }^0$. Various details relating to the background subtractions, radiative corrections and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well known $\Delta (1232)$ resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios $R_{EM}$ and $R_{SM}$ along with the magnetic transition form factor $G_M^{\ast }$. It is found that the rapid fall off of the $\Delta (1232)$ contribution continues into this region of momentum transfer and that other resonances

arXiv comment41 pages including numerical cross section tables, updates include new phenomenological fit for multipole extraction in addition to simplified previous method, These fits are seen in figures 24,26 and 27 and the values are reported in Table VIII

References in corpus (28)

• The Cosmological Parameters 2006
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• A unitary isobar model for pion photo- and electroproduction on the proton up to 1 GeV
• Electromagnetic excitation of the Delta(1232)-resonance
• Meson-exchange Model for $\pi N$ scattering and $\gamma N->\pi N$ reaction
• Measurements of electron-proton elastic cross sections for $0.4<Q^2<5.5(GeV/c{)}^2$
• $Q^2$ Dependence of Quadrupole Strength in the ${\gamma }^{\ast }p\to {\Delta }^{+}(1232)\to p{\pi }^0$ Transition
• Dynamical Study of the Delta Excitation in N(e,e' pi) Reactions
• Electroproduction of the Delta Resonance at High Momentum Transfer
• Radiative Corrections to Electron-Proton Scattering
• Electromagnetic Meson Production in the Nucleon Resonance Region
• Charged pion form factor between $Q^2$=0.60 and 2.45 GeV${}^2$. I. Measurements of the cross section for the ${}^1$H($e,e^{\prime }{\pi }^{+}$)$n$ reaction
• Investigation of the conjectured nucleon deformation at low momentum transfer
• Measurement of the N to Delta(1232) Transition at High Momentum Transfer by pi0 Electroproduction
• The N to Delta electromagnetic transition form factors from Lattice QCD
• Measurement of the recoil polarization in the p (\vec e, e' \vec p) pi^0 reaction at the Δ(1232) resonance
• Electroexcitation of the P33(1232), P11(1440), D13(1520), S11(1535) at Q^2=0.4 and 0.65(GeV/c)^2
• Recoil Polarization for Delta Excitation in Pion Electroproduction
• Lowest Q^2 Measurement of the gamma*p -> Delta Reaction: Probing the Pionic Contribution
• QED Radiative Corrections in Processes of Exclusive Pion Electroproduction
• Resonance Contributions to $\eta$ Photoproduction on Protons Found Using Dispersion Relations and an Isobar Model
• Measurement of the LT-asymmetry in π^0 electroproduction at the energy of the Δ(1232) resonance
• Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer
• Determination of quadrupole strengths in the gamma*p-->Delta(1232) transition at Q2= 0.20 (GeV/c)2
• Approach to Perturbative Results in the N-Delta Transition
• Measurements of the Delta(1232) Transition Form Factor and the Ratio sigma_nσ_p From Inelastic Electron-Proton and Electron-Deuteron Scattering
• Longitudinal-Transverse Separations of Structure Functions at Low $Q^2$ for Hydrogen and Deuterium
• Two-photon-exchange effects in the electro-excitation of the $\Delta$ resonance

Cited by in corpus (26)

• Studies of Nucleon Resonance Structure in Exclusive Meson Electroproduction
• Electroexcitation of nucleon resonances
• Electromagnetic Excitation of Nucleon Resonances
• Nucleon electromagnetic form factors and electroexcitation of low lying nucleon resonances in a light-front relativistic quark model
• Strong QCD Insights from Excited Nucleon Structure Studies with CLAS and CLAS12
• A model for the Delta(1600) resonance and gamma N -> Delta(1600) transition
• Octet to decuplet electromagnetic transition in a relativistic quark model
• Nucleon resonance contributions to unpolarised inclusive electron scattering
• Electromagnetic Transition Form Factors of Baryon Resonances
• Results from the N* program at JLab
• Nucleon resonances in Compton scattering
• Effects of a spin-flavour dependent interaction on light-flavoured baryon helicity amplitudes
• Electroexcitation of nucleon resonances of the [70,1-] multiplet in a light-front relativistic quark model
• Electroexcitation of the ${\Delta }^{+}(1232)$ at low momentum transfer
• Measurements of the γ* p --> Δ(1232) reaction at low Q2
• Electroexcitation of the Delta(1232)3/2+ and Delta(1600)3/2+ in a light-front relativistic quark model
• Impact of JLab data on the determination of GPDs at zero skewness and new insights from transition form factors $N\to \Delta$
• Electroexcitation of nucleon resonances in a light-front relativistic quark model
• Electromagnetic transition form factors, $E2/M1$ and $C2/M1$ ratios of the baryon decuplet
• Nucleon to $\Delta$ transition form factors and empirical transverse charge densities
• Target and beam-target spin asymmetries in exclusive pion electroproduction for $Q^2>1$ GeV${}^2$. II. $ep\to e{\pi }^{0}p$
• Two Photon Exchange for Exclusive Pion Electroproduction
• Low-Q^2 scaling behavior of the form-factor ratios for the NΔ(1232)-transition
• Gauge- and point-invariant vertices of nucleon-to-resonance interactions
• Near Threshold Neutral Pion Electroproduction at High Momentum Transfers and Generalized Form Factors
• Pion electroproduction measurements in the nucleon resonance region