Download or read book Measurements of the Polarisation of the Recoil Proton in Elastic Electron Proton Scattering at Q2 written by H. C. Kirkman and published by . This book was released on 1970 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of the Polarisation of the Recoil Proton in Elastic Electron Proton Scattering at 92 written by H. C. Kirkman and published by . This book was released on 1970 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Measurements of the Recoil Proton Polarisation in Elastic Electron Proton Scattering written by Robert Railton and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of the Polarisation of the Recoil Proton in Elastic Proton Scattering at Q 2 written by H. C. Kirkman and published by . This book was released on 1970 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of the Proton Electromagnetic Form Factor Ratio From Elastic E P E P Scattering at Momentum Transfer Q2 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents. Electromagnetic probes are traditionally preferered to the hadronic beams. The electromagnetic interaction is a powerful tool for investigating the nucleon structure since it is well understood and it reveals observables that can be directly interpreted in terms of the current carried by the quarks. Elastic scattering leads to the form factors that describe the spatial charge and current distributions inside the nucleon. The reaction mechanism is assumed to be one photon exchange, the electromagnetic interaction is exactly calculable in QED, and one can safely extract the information on the hadronic vertex. The most important feature of early measurements of proton form factor ratio GEp/GMp with recoil polarization technique at Q2 up to 5.6 (GeV/c)2 is the sharp decline of the ratio with Q2 increases, indicating that GEp falls much faster than GMp. This contradicts to data obtained by Rosenbluth separation method. An intriguing question was whether GEp will continue to decrease or become constant when Q2 increases. New set of measurements of proton form factor ratio GEp/GMp at Q2 = 2.5, 5.2, 6.7 and 8.5 (GeV/c)2 have been conducted at JLab Hall C using ~85% longitudinally polarized electron elastic scattering from unpolarized hydrogen target. Recoil protons were detected in the HMS magnetic spectrometer with the standard detector package, combined with newly installed trigger scintillators and Focal Plane Polarimeter. The BigCal electromagnetic calorimeter (1744 channel) have been used for electron detection. Data obtained in this experiment show that GEp/GMp ratio continued to drop with Q2 and may cross 'zero' at Q2> 10-15 (GeV/c)2. Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton form factor ratio GEp/GMp obtained from cross section and polarization measurements. It was assumed that the two photon exchange contribution might be responsible for difference of GEp/GMp ratio obtained by Rosenbluth separation method and recoil polarization technique. The kinematical dependence of polarization transfer observables in elastic electron-proton scattering at Q2 = 2.5 (GeV/c)2 have been used in search of effects of 2[gamma] contribution. For a wide range of values of the virtual photon polarization [Sigma] ([Sigma] = 0.15, 0.63, and 0.77), the proton form factor ratio and longitudinal polarization transfer component were measured with statistical uncertainties of ±0.01 and ±0.005, respectively. Our data provide significant constraints on models of nucleon structure.
Download or read book A Measurement of the Two photon Exchange Effect in Elastic Electron proton Scattering with OLYMPUS written by Rebecca Lynn Russell and published by . This book was released on 2016 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastic electron-proton scattering has long been the tool of choice for the study of the proton form factors, GE(Q 2 ) and GM(Q2 ), which describe the electric and magnetic distributions of the proton as a function of momentum transfer. Recent experiments, measuring the form factors from polarization observables in polarized elastic electron-proton scattering, have found values of the ratio GE(Q2 )/GM(Q2) at high Q2 that contradict the results from unpolarized measurements. A proposed explanation for this discrepancy is the unaccounted two-photon exchange radiative correction, which could affect the unpolarized measurements. As this effect is currently not possible to calculate in a model-independent way, the OLYMPUS experiment was designed to make a direct measurement of it by measuring the elastic positron-proton to electron-proton scattering cross section ratio. The experiment was run in 2012 at DESY using the BLAST spectrometer and the DORIS positron and electron beams at 2 GeV incident on a gaseous hydrogen target. To analyze the data, a careful reconstruction of the scattering events, detailed simulation of the experimental setup, and full radiative corrections to the measured cross sections were performed. Preliminary results for the experiment show a statistically significant two-photon exchange effect, increasing over the measurement range of 0.6 GeV2
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Elastic K proton Scattering at 910 MeV c written by Warner Hirsch and published by . This book was released on 1963 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio at High Momentum Transfer written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electromagnetic form factors are fundamental properties of the nucleon that describe the effect of its internal quark structure on the cross section and spin observables in elastic lepton-nucleon scattering. Double-polarization experiments have become the preferred technique to measure the proton and neutron electric form factors at high momentum transfers. The recently completed GEp-III experiment at the Thomas Jefferson National Accelerator Facility used the recoil polarization method to extend the knowledge of the proton electromagnetic form factor ratio GpE/GpM to Q2 = 8.5 GeV2. In this paper we present the preliminary results of the experiment.
Download or read book Measurement of the Recoil Proton Polarization in Elastic P Scattering at T written by P. Bareyre and published by . This book was released on 1964 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to High Momentum Transfer written by and published by . This book was released on 2010 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions of the squared four-momentum transfer Q2 between the electron and the proton. The two main classes of observables of this reaction are the scattering cross section and polarization asymmetries, both of which are sensitive to the form factors in different ways. When considering large f momentum transfers, double-polarization observables offer superior sensitivity to the electric form factor. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton at high momentum transfer using the recoil polarization technique. A polarized electron beam was scattered from a liquid hydrogen target, transferring polarization to the recoiling protons. These protons were detected in a magnetic spectrometer which was used to reconstruct their kinematics, including their scattering angles and momenta, and the position of the interaction vertex. A proton polarimeter measured the polarization of the recoiling protons by measuring the azimuthal asymmetry in the angular distribution of protons scattered in CH2 analyzers. The scattered electron was detected in a large acceptance electromagnetic calorimeter in order to suppress inelastic backgrounds. The measured ratio of the transverse and longitudinal polarization components of the scattered proton is directly proportional to the ratio of form factors GpE=GpM. The measurements reported in this thesis took place at Q2 =5.2, 6.7, and 8.5 GeV2, and represent the most accurate measurements of GpE in this Q2 region to date.
Download or read book Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to High Momentum Transfer written by Andrew James Ruehe Puckett and published by . This book was released on 2010 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions of the squared four-momentum transfer Q2 between the electron and the proton. The two main classes of observables of this reaction are the scattering cross section and polarization asymmetries, both of which are sensitive to the form factors in different ways. When considering large momentum transfers, double-polarization observables offer superior sensitivity to the electric form factor. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton at high momentum transfer using the recoil polarization technique. A polarized electron beam was scattered from a liquid hydrogen target, transferring polarization to the recoiling protons. These protons were detected in a magnetic spectrometer which was used to reconstruct their kinematics, including their scattering angles and momenta, and the position of the interaction vertex. A proton polarimeter measured the polarization of the recoiling protons by measuring the azimuthal asymmetry in the angular distribution of protons scattered in CH2 analyzers. The scattered electron was detected in a large-acceptance electromagnetic calorimeter in order to suppress inelastic backgrounds. The measured ratio of the transverse and longitudinal polarization components of the scattered proton is directly proportional to the ratio of form factors GE/Gpm. The measurements reported in this thesis took place at Q2 =5.2, 6.7, and 8.5 GeV 2, and represent the most accurate measurements of G' in this Q2 region to date.
Download or read book Measurement of the Recoil Proton Polarization in Elastic P Scattering at T 410 and 492 Mev written by P. Bareyre and published by . This book was released on 1965 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polarization of Recoil Protons in Pion Proton Elastic Scattering at 523 572 and 689 Mev thesis written by and published by . This book was released on 1963 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Angular distributions of recoil-proton polarization for elastic scattering of positive and negative pi mesons on protons were measured at 523, 572, and 689 Mev incidentpion kinetic energy. The pion source was an internal target of the Berkeley Bevatron. Polarization measurements were made by observing the azimuthal asymmetry of sample angular distributions of recoil protons that scatter in large carbon-plate spark chambers. The spark chambers proved to be very suitable polarization analyzerdetectors. The spark chambers were triggered by an array of scintillation and Cerenkov counters that identified the particles entering the chambers as recoil protons from elastic pion-proton scattering. Two plausible nonunique sets of phase shifts were obtained by employing: restrictive assumptions related to the higher resonances, available pion-proton total and differential cross sections measured at nearby energies, and the measurements of this experiment. One set is characterized by a J = 3/2, T = 1/2, D-wave resonance; the other set is characterized by a J = 3/2, T = 1/2, P-wave resonance at 600-Mev incidentpion energy. 38 references. (auth).
Download or read book Proton G E G M from Beam target Asymmetry written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio of the proton's electric to magnetic form factor, G{sub E}/G{sub M}, can be extracted in elastic electron-proton scattering by measuring either cross sections, beam-target asymmetry or recoil polarization. Separate determinations of G{sub E}/G{sub M} by cross sections and recoil polarization observables disagree for Q2> 1 (GeV/c)2. Measurement by a third technique might uncover an unknown systematic error in either of the previous measurements. The beam-target asymmetry has been measured for elastic electron-proton scattering at Q2 = 1.51 (GeV/c)2 for target spin orientation aligned perpendicular to the beam momentum direction. This is the largest Q2 at which G{sub E}/G{sub M} has been determined by a beam-target asymmetry experiment. The result, [mu]G{sub E}/G{sub M} = 0.884 +/- 0.027 +/- 0.029, is compared to previous world data.
Download or read book Polarization of Recoil Protons in Pion proton Elastic Scattering at 523 572 and 689 MeV written by Richard Domingo Eandi and published by . This book was released on 1963 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Baryons 95 written by Benjamin F. Gibson and published by World Scientific. This book was released on 1996 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt:
