Recent results on the nucleon resonance spectrum and structure from the CLAS detector

Abstract

The CLAS detector at Jefferson Lab has provided the dominant part of all available worldwide data on exclusive meson electroproduction off protons in the resonance region. New results on the ${\gamma }_{v}p{N}^{\ast }$ transition amplitudes (electrocouplings) are available from analyses of the CLAS data and will be presented. Their impact on understanding of hadron structure will be discussed emphasizing the credible access to the dressed quark mass function that has been achieved for the first time by a combined analysis of the experimental results on the electromagnetic nucleon elastic and $N\to N^{\ast }$ transition form factors. We will also discuss further convincing evidences for a new baryon state $N^{{}^{\prime }}(1720)3/2^{+}$ found in a combined analysis of charged double pion photo- and electroproduction cross sections off the protons.

Invited Talk Paper for the 21st International Conference on Few-Body Problems in Physics, Chicago, Illinois, USA

References in corpus (6)

• A study of the $P_{11}(1440)$ and $D_{13}(1520)$ resonances from CLAS data on $ep\to e^{\prime }{\pi }^{+}{\pi }^{-}{p}^{\prime }$
• Dynamical Coupled-Channels Effects on Pion Photoproduction
• A systematic study of longitudinal and transverse helicity amplidutes in the hypercentral Constituent Quark Model
• Model Analysis of the $ep\to e{p}^{\prime }{\pi }^{+}{\pi }^{-}$ Electroproduction Reaction on the Proton
• Measurements of $ep\to e^{\prime }{\pi }^{+}n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS
• Extracting meson-baryon contributions to the electroexcitation of the $N(1675){\frac{5}{2}}^{-}$ nucleon resonance

Cited by in corpus (15)

• Diquark Correlations in Hadron Physics: Origin, Impact and Evidence
• Spectrum of light- and heavy-baryons
• Empirical Consequences of Emergent Mass
• Studying the P_c(4450) resonance in J/psi photoproduction off protons
• Parity partners in the baryon resonance spectrum
• Nucleon elastic form factors at accessible large spacelike momenta
• Evidence for the $N^{\prime }(1720)3/2^{+}$ Nucleon Resonance from Combined Studies of CLAS ${\pi }^{+}{\pi }^{-}p$ Photo- and Electroproduction Data
• Measurements of $ep\to e^{\prime }{\pi }^{+}{\pi }^{-}{p}^{\prime }$ Cross Sections with CLAS at $1.40<W<2.0$ GeV and $2.0<Q^2<5.0$ GeV${}^2$
• First results on nucleon resonance photocouplings from the $\gamma p\to {\pi }^{+}{\pi }^{-}p$ reaction
• Nucleon resonance contributions to unpolarised inclusive electron scattering
• Nucleon resonances in Compton scattering
• N* Structure and Strong QCD
• Measurements of the ${\gamma }_{v}p\to p^{\prime }{\pi }^{+}{\pi }^{-}$ 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
• Low-$Q^2$ empirical parametrizations of the $N^{\ast }$ helicity amplitudes
• Studying the Pc(4450) resonance in J/psi photoproduction off protons