Related papers: Polarization Observables for Kaon Photoproduction …
Little information is known about the polarization of gluons inside a longitudinally polarized proton. We investigate the sensitivity of photoproduction experiments with both beam and target longitudinally polarized to the polarization of…
Generalized parton distributions describe the correlations between the longitudinal momentum and the transverse position of quarks and gluons in a nucleon. They can be constrained by measuring photon leptoproduction observables, arising…
Precision measurements of the structure of nucleons and nuclei in the regime of strong interaction QCD are now possible with the availability of high current polarized electron beams, polarized targets, and recoil polarimeters, in…
Polarization asymmetries in photoproduction of high transverse momentum mesons are a flavor sensitive way to measure the polarized quark distributions. We calculate the expected asymmetries in several models, and find that the asymmetries…
Developments in strangeness photo- and electro- production off the proton, as investigated using the CLAS system in Hall B at Jefferson Lab, are discussed in this paper. By measuring sufficient spin observables one can decompose the…
First comprehensive data on the evolution of nucleon resonance photocouplings with photon virtuality Q^2 are presented for excited proton states in the mass range from 1.4 to 2.0 GeV. N^* photocouplings were determined in phenomenological…
Recent measurements using the CLAS detector at Jefferson Lab of the reactions $\vec\gamma + p \to K^+ + \vec\Lambda$ and $\vec\gamma + p \to K^+ + \vec\Sigma^0$ have been used to extract the spin transfer coefficients $C_x$ and $C_z$ for…
The purpose of this contribution is to stress the great importance of polarization observables for the study of nucleon resonances, in particular in the case of deuteron and proton probes. Polarization observables play a unique role in…
Advances in the exploration of the spectrum and structure of the excited states of the nucleon from experiments with electromagnetic probes on proton targets are presented. Impressive progress has been achieved in the studies of exclusive…
Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental program at the next generation of lepton accelerators. In the context of the Hadronic Physics program at the Jefferson Laboratory…
Recent results from JLab on the electromagnetic excitation of nucleon resonances are presented, and confronted with theoretical predictions. Preliminary data in the search for undiscovered states are discussed as well.
Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom…
There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has been greatly improved by performing double polarization experiments, in…
In the framework of the k_t-factorization approach, the production of $\Upsilon mesons at the Fermilab Tevatron and CERN LHC is considered, and the predictions on the spin alignment parameter $\alpha$ are presented. We argue that measuring…
We propose to extend the investigations of the eta meson production in nucleon-nucleon collisions by studying single and double polarization observables. Over the last years, the eta meson has been studied at several different experiments…
Experiments on pion (Goldstone Boson) photoproduction from the nucleon tests the ability to make QCD predictions at confinement scale energies. Experiments with both polarized beams and targets have the potential sensitivity to demonstrate…
The CBELSA/TAPS experiment with a longitudinally or transversely polarized target and an energy tagged, linearly or circularly polarized photon beam allows the measurement of a large set of polarization observables. Due to its good energy…
The polarizations of Y(nS) (n=1,2,3) and prompt J/\psi and \psi(2S), as well as the differential cross section of the Y(nS), are measured in proton-proton collisions at sqrt(s) = 7 TeV, using a dimuon data sample collected by the CMS…
A novel approach that allows access to long-sought information on the Hyperon-Nucleon (YN) interaction was developed by producing a hyperon beam within a few-body nuclear system, and studying final-state interactions. The determination of…
We investigate the sea quark polarization in the nucleon by means of a combined next to leading order analysis to the recently enlarged set of inclusive and semi-inclusive polarized deep inelastic scattering data. Using the Lagrange…