[en] A review is given of electroproduction and photoproduction at photon energies extending from the resonance region up to about 10 GeV. Comparisons are made between the various experiments and the appropriate theories in an attempt to understand more about the different production mechanisms - s channel resonances, t and u channel exchanges and quark-parton effects. (orig.)

[en] The HKS (Jlab E01-011) experiment on spectroscopy of Lambda-hypernuclei using (e,e'K+) reaction was successfully carried out in 2005. This paper gives a brief description of the experiment and its technique and shows some of the preliminary spectra that are still under analysis.

[en] The derivation of proton and neutron electromagnetic form factors from elastic electron scattering on proton and deuteron targets has already been the object of detailed discussions in excellent reviews. We shall thus concentrate our attention on low-energy inelastic electron-nucleon scattering and emphasize those form factors which can be obtained from such experiments. In particular we shall deal with the elastic form factor of the pion, the N-Δ transition from factors, and, via current algebra, with the axial structure functions of the nucleon. (orig.)

No abstract available

[en] Preliminary results on the unseparated ratio of π^- and π⁺ electroproduction off deuterium in the experiment E93021 at Jefferson Lab are presented

[en] The Callan-Gross relation, originally based on the parton model, predicts that, in (say) electroproduction, sigmasub(L)/sigmasub(T) = 0. When QCD corrections are taken into account this relation gets modified by terms of order αsub(c)(Q²). We define R approximately sigmasub(L)/sigmasub(T) to measure the violation of the Callan-Gross relation. One can obtain exactly the behaviour of R(x,Q²) at the endpoints x = 0,1 from QCD. This will incidentally allow us to write a simple and explicit parametrization, which is exact at x = 0,1 and a good approximation at all other x. We will carry out the analysis for proton targets and e, μ projectiles; the extension to ν scattering or other targets is straightforward

[en] Physics analysis of recent CLAS data on double pion production by virtual photons is presented

[en] In these proceedings we present preliminary π^± electroproduction cross sections off protons in the kinematical area of 1.4 GeV < W < 1.8 GeV² < Q² < 1.1 GeV². Our Results extend the kinematical coverage for this exclusive channel with respect to previous measurements. Furthermore, the π^± electroproduction cross sections were obtained for Q²-bins of much smaller size. The future analysis of this data within the framework of the JLAB-MSU reaction model (JM) will considerably improve our knowledge on the Q² evolution of the transition γ₁NN* electrocouplings, in particular for the resonances with massive 1.6 GeV.

No abstract available

[en] We report on meson spectroscopy using the CLAS at Jefferson Lab. We study photo-production of exotic mesons and strangeonia on the largest data sample ever to be produced at photon energies of about 5 GeV. We also describe an experiment to continue meson spectroscopy at CLAS12 (CLAS energy upgrade) using electroproduction at very low Q2 ('quasireal photons') up to photon energies of 10 GeV.