Rosenbluth separation of the ${\pi }^0$ electroproduction cross section

Abstract

We present deeply virtual ${\pi }^0$ electroproduction cross-section measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5 to 2 GeV${}^2$, obtained from experiment E07-007 that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics. An indication of a non-zero longitudinal contribution is provided by the interference term ${\sigma }_{LT}$ also measured. Results are compared with several models based on the leading twist approach of Generalized Parton Distributions (GPDs). In particular, a fair agreement is obtained with models where the scattering amplitude is described by a convolution of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral pion electroproduction may offer the exciting possibility of accessing transversity GPDs through experiment.

Submitted to Physical Review Letters

References in corpus (3)

• Nucleon Tensor Charge from Exclusive ${\pi }^o$ Electroproduction
• Measurement of Azimuthal Asymmetries With Respect To Both Beam Charge and Transverse Target Polarization in Exclusive Electroproduction of Real Photons
• Measurement of Exclusive ${\pi }^0$ Electroproduction Structure Functions and their Relationship to Transversity GPDs

Cited by in corpus (12)

• An introductory lecture on Generalised Parton Distributions
• Exclusive $\eta$ electroproduction at $W>2$ GeV with CLAS and transversity generalized parton distributions
• Transition GPDs and exclusive electroproduction of $\pi -\Delta (1232)$ final states
• u-Channel Color Transparency Observables
• Generalized Parton Distributions from charged current meson production
• Exclusive ${\pi }^0$ production at EIC of China within handbag approach
• Study of transversity GPDs from pseudoscalar mesons production at EIC of China
• Spin Orbit Correlations and the Structure of the Nucleon
• Twist-3 contribution to deeply virtual electroproduction of pions
• Lepton-pair production in hard exclusive hadron-hadron collisions
• Study of the Transverse-Momentum-Dependent structure of the nucleon in Semi-Inclusive DIS
• Wide-angle photoproduction of the ${\eta }^{\prime }$-meson and its gluon content