Electric charge of elementary particles

Nucleon electromagnetic form factors

“…In the same paper the authors also pointed out that the best way to obtain the proton charge FF is with polarization experiments, especially by measuring the polarization of the recoil proton. Further in a review paper in 1974 Akhiezer and Rekalo [Akh74] discussed specifically the interest of measuring an interference term of the form G E G M by measuring the transverse component of the recoiling proton polarization in the ep → e p reaction at large Q 2 , to obtain G E in the presence of a dominating G M . In 1969, in a review paper Dombey [Dom69] also discussed the virtues of measuring polarization observables in elastic and inelastic lepton scattering; however his emphasis was to do these measurements with a polarized lepton on a polarized target.…”

Flavor decomposition of the nucleon electromagnetic form factors at lowQ2

“…The electrons transfer their polarization to the unpolarized protons. By simultaneously measuring the transverse, P t , and longitudinal, P l , polarization components of the recoil proton, one can determine the ratio µ p G p E /G p M in the OPE [2,14,15]:…”

Polarization Transfer in theHe4(e→,e′p→)Paolone1, Malace2, Strauch3 et al. 2010Phys. Rev. Lett.10041051View full textAdd to dashboardCite

“…For over a decade, access to high-quality polarized electron beams has allowed the nucleon's electromagnetic properties to be explored through measurement of polarization observables. In elastic electron-nucleon scattering, the polarizationtransfer technique allows measurement of the Sachs formfactor ratio G E /G M , that is directly proportional to the ratio of transverse and longitudinal polarization observables P ′ x /P ′ z in the single-photon exchange approximation [1,2]. This technique [3] benefits from a large cancellation of systematic uncertainties, unlike the Rosenbluth separation technique, which relies on repeated crosssection measurements.…”