## Measurements of the $\gamma_{v} p \rightarrow p' \pi^{+} \pi^{-}$ cross section with the CLAS detector for $0.4$ GeV$^{2}$ $< Q^{2} <$ $1.0$ GeV$^{2}$ and $1.3$ GeV $< W <$ $1.825$ GeV

### Abstract

International audienceNew results on the single-differential and fully integrated cross sections for the process γvp→p′π+π− are presented. The experimental data were collected with the CLAS detector at Jefferson Laboratory. Measurements were carried out in the kinematic region of the reaction invariant mass W from 1.3 to 1.825 GeV and the photon virtuality Q2 from 0.4 to 1.0 GeV2. The cross sections were obtained in narrow Q2 bins (0.05 GeV2) with the smallest statistical uncertainties achieved in double-pion electroproduction experiments to date. The results were found to be in agreement with previously available data where they overlap. A preliminary interpretation of the extracted cross sections, which was based on a phenomenological meson-baryon reaction model, revealed substantial relative contributions from nucleon resonances. The data offer promising prospects to improve knowledge on the Q2 evolution of the electrocouplings of most resonances with masses up to ∼1.8 GeV

Topics: nucleon resonance, photon, overlap, kinematics, statistical, meson baryon, electroproduction, up: mass, Hadronic Physics and QCD, * Automatic Keywords *, CLAS, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]
Publisher: 'American Physical Society (APS)'
Year: 2018
DOI identifier: 10.1103/PhysRevC.98.025203
OAI identifier: oai:HAL:hal-01815231v1
Provided by: HAL-CEA