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

41 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 (5)

• Electromagnetic excitation of the Delta(1232)-resonance
• 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
• Lowest Q^2 Measurement of the gamma*p -> Delta Reaction: Probing the Pionic Contribution
• Determination of quadrupole strengths in the gamma*p-->Delta(1232) transition at Q2= 0.20 (GeV/c)2
• Longitudinal-Transverse Separations of Structure Functions at Low $Q^2$ for Hydrogen and Deuterium

Cited by in corpus (8)

• Strong QCD Insights from Excited Nucleon Structure Studies with CLAS and CLAS12
• Electromagnetic Transition Form Factors of Baryon Resonances
• Impact of JLab data on the determination of GPDs at zero skewness and new insights from transition form factors $N\to \Delta$
• Electromagnetic transition form factors, $E2/M1$ and $C2/M1$ ratios of the baryon decuplet
• Target and beam-target spin asymmetries in exclusive pion electroproduction for $Q^2>1$ GeV${}^2$. II. $ep\to e{\pi }^{0}p$
• 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