Download or read book Recoil Proton Polarization in High Energy Deuteron Photodisintegration with Circularly Polarized Photons written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.
Download or read book Polarization Measurements in High Energy Deuteron Photodisintegration written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present measurements of the recoil proton polarization for the d(polarized y, polarized p)n reaction at thetac.m. = 90 degrees for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization py vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(y, p)n cross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.
Download or read book Angular Dependence of Recoil Proton Polarization in High energy gamma D to P N written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We measured the angular dependence of the three recoil proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.
Download or read book Polarization in Photodisintegration of the Deuteron written by and published by . This book was released on 2001 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recoil proton polarization was measured in deuteron photodisintegration at theta{sub cm} = 90{sup o} for photon energies up to 2.4 GeV. The induced polarization py is consistent with vanishing above 1 GeV, in surprising disagreement with meson-baryon calculations. From pQCD it is generally expected that hadron helicity is conserved, but, the polarization transfer observables do not vanish. As the data are inconsistent with existing meson baryon model predictions, and with expectations from pQCD, we suggest that nonperturbative quark models will be needed to understand the underlying reaction dynamics.
Download or read book Photodisintegration of the Deuteron with Polarized Photons from LEGS written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An experiment is described which will measure the d(.gamma., p) reaction with polarized photon beams from LEGS ranging in energy from 50 MeV to 530 MeV. The data will yield a new high-resolution high-statistics determination of the total unpolarized cross section, will isolate for the first time the polarization dependent part of the reaction, and will measure the photon-beam asymmetry with much higher resolution and accuracy than available from existing data. These will provide one of the most stringent tests for models of the nuclear force. In addition, high-resolution data will be taken with both linear and circularly-polarized .gamma. rays to search for the effects of bibaryons.
Download or read book Polarization Transfer in Proton Compton Scattering at High Momentum Transfer written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Compton scattering from the proton was investigated at s = 6.9 GeV2 and t = -4.0 TeV2 via polarization transfer from circularly polarized incident photons. The longitudinal and transverse components of the recoil proton polarization were measured. The results are in excellent agreement with a prediction based on a reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton and in disagreement with a prediction of pQCD based on a two-gluon exchange mechanism.
Download or read book Polarization of Protons from d P Reactions at 21 Mev written by Edmund T. Boschitz and published by . This book was released on 1964 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Measurement of the Polarization of the Proton from the High Energy Photodisintegration of Deuterium written by Paul Gorenstein and published by . This book was released on 1962 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photodisintegration of the deuteron by polarized photons written by and published by . This book was released on 1979 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of the polarization of protons from deuteron photodisintegration for photon energies between 282 and 405 MeV written by Karl Heinz Kissler and published by . This book was released on 1968 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measuraements of the Polarization of Protons from Deuteron Photodisintegration for Photon Energies Between 282 and 405 MeV written by and published by . This book was released on 1969 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proton Polarization in Neutral Pion Photo production written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present measurements of recoil proton polarization for 1H({rvec {gamma}}, {rvec p})[pi]° in and above the resonance region. These are the first data in this reaction for polarization transfer with circularly polarized photons. The results are compared to phase shift analyses and quark model calculations.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scattering of High Energy Circularly Polarized Photons by Polarized Electrons written by Forrest Pierce Clay and published by . This book was released on 1952 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polarization Transfer in Wide angle Compton Scattering and Single pion Photoproduction from the Proton written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The WACS polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of [theta]Pcm = 70°. The longitudinal transfer KLL, measured to be 0.645 ± 0.059 ± 0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton. However, the observed value is ~3 times larger than predicted by the GPD-based calculations, which indicates a significant unknown contribution to the scattering amplitude.
Download or read book Correlated Proton proton Pairs from the High energy Photodisintegration of Light Nuclei written by Alan Virgil Larson and published by . This book was released on 1961 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Targets of He, Li, C, and Al were irradiated by bremsstrahlung of 257 Mev maximum photon energy. Photodisintegrations which involve two fast protons were observed. Energy and angular distributions of the coincident protons, one of which was always observed at a laboratory angle corresponding roughly to 90 degrees in the center of mass of the two protons, were measured. The primary absorption of the photon occurs on neutron-proton pairs. The proton-proton pairs arise from subsequent internal scattering of the primary photoneutron from other protons in the nucleus. No evidence is seen that mesons are reabsorbed on nucleon pairs which do not include the parent nucleon. An upper limit is established for this process. This experiment supports the photomeson production models which do not depend upon the true absorption of mesons as they pass through nuclear matter. (Author).
Download or read book Proton Polarization Angular Distribution in Deuteron Photo Disintegration written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The apparent scaling in 90 cm deuteron photodisintegration, first observed several years ago at SLAC, has lead to several related experiments and a number ot theoretical calculations. We have in the past year measured in Hall A, with up to 2.5-GeV photons, cross sections at large angles and the proton polarization at 90cm. Verypreliminary online analysis of the induced polarizations yields the very surprising result that theinduced polarizations apparently vanish starting at about the same energy at whichthe existing cross section data start to scale, to follow the constituent countingrules. Given this result, we propose further measurements to see if this observationholds at other angles.
