Showing papers by "W. Meyer published in 2000"
Stanford University1, American University2, California Institute of Technology3, University of Wisconsin-Madison4, University of Massachusetts Amherst5, University of Virginia6, University of Michigan7, University of Liverpool8, Smith College9, Centre national de la recherche scientifique10, University of California, Los Angeles11, Thomas Jefferson National Accelerator Facility12, College of William & Mary13, Florida International University14, Ruhr University Bochum15, Kent State University16, Los Alamos National Laboratory17, University of Basel18, Old Dominion University19
TL;DR: The ratio g 1 F 1 (GeV/c) has been measured over the range 0.03 g 1F 1 to be consistent with no Q2-dependence at fixed x in the deep-inelastic region Q2 > 1 as discussed by the authors.
217 citations
TL;DR: The helicity dependence of the single pion photoproduction on the proton has been measured for the first time and the main contributions to the Gerasimov-Drell-Hearn sum rule and the forward spin polarizability gamma(0).
Abstract: The helicity dependence of the single pion photoproduction on the proton has been measured in the energy range from 200 to 450 MeV for the first time. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a frozen-spin target. The data obtained provide new information for multipole analyses of pion photoproduction and determine the main contributions to the Gerasimov-Drell-Hearn sum rule and the forward spin polarizability gamma(0).
83 citations
21 Mar 2000-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, the beam polarisation was determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed.
Abstract: A muon beam polarimeter was built for the SMC experiment at the CERN SPS, for beam energies of 100 and 190 GeV. The beam polarisation is determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed. At muon energies of 100 and 190 GeV the measured polarisation is Pμ=−0.80±0.03 (stat.)±0.02 (syst.) and Pμ=−0.797±0.011 (stat.)±0.012 (syst.), respectively. These results agree with measurements of the beam polarisation using a shape analysis of the decay positron energy spectrum.
21 citations
18 citations
Posted Content•
TL;DR: The TESLA-N linear collider as mentioned in this paper is a state-of-the-art collider with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable energies.
Abstract: Measurements of polarized electron-nucleon scattering can be realized at the TESLA linear collider facility with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable energies. Longitudinally polarized electrons, accelerated as a small fraction of the total current in the e+ arm of TESLA, can be directed onto a solid state target that may be either longitudinally or transversely polarized. A large variety of polarized parton distribution and fragmentation functions can be determined with unprecedented accuracy, many of them for the first time. A main goal of the experiment is the precise measurement of the x- and Q^2-dependence of the experimentally totally unknown quark transversity distributions that will complete the information on the nucleon's quark spin structure as relevant for high energy processes. Comparing their Q^2-evolution to that of the corresponding helicity distributions constitutes an important precision test of the predictive power of QCD in the spin sector. Measuring transversity distributions and tensor charges allows access to the hitherto unmeasured chirally odd operators in QCD which are of great importance to understand the role of chiral symmetry. The possibilities of using unpolarized targets and of experiments with a real photon beam turn TESLA-N into a versatile next-generation facility at the intersection of particle and nuclear physics.
6 citations
Journal Article•
5 citations