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Journal or Publication Title: | Physics Letters B | ||||
Publisher: | ELSEVIER SCIENCE BV | ||||
Place of Publication: | AMSTERDAM | ||||
Volume: | 513 | ||||
Number of Issue or Book Chapter: | 3-4 | ||||
Page Range: | pp. 301-310 | ||||
Date: | 2001 | ||||
Institutions: | Physics > Institute of Theroretical Physics > Chair Professor Schäfer > Group Andreas Schäfer | ||||
Identification Number: |
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Keywords: | VIRTUAL COMPTON-SCATTERING; VECTOR-MESONS; ELECTROPRODUCTION; LEPTOPRODUCTION; PHOTONS; NUCLEON; HERA; PHOTOPRODUCTION; POLARIZATION; HYDROGEN; lepton-nucleon scattering; rho production; asymmetries; photoabsorbtion | ||||
Dewey Decimal Classification: | 500 Science > 530 Physics | ||||
Status: | Published | ||||
Refereed: | Yes, this version has been refereed | ||||
Created at the University of Regensburg: | Yes | ||||
Item ID: | 73504 |
Abstract
Evidence for a positive longitudinal double-spin asymmetry <A(l)(rho)> = 0.24 +/- 0.11(stat) +/- 0.02(syst) in the cross section for exclusive diffractive rho (0)(770) vector-meson production in polarised lepton-proton scattering was observed by the HERMES experiment. The longitudinally polarised 27.56 GeV HERA positron beam was scattered off a longitudinally polarised pure hydrogen gas target. ...

Abstract
Evidence for a positive longitudinal double-spin asymmetry <A(l)(rho)> = 0.24 +/- 0.11(stat) +/- 0.02(syst) in the cross section for exclusive diffractive rho (0)(770) vector-meson production in polarised lepton-proton scattering was observed by the HERMES experiment. The longitudinally polarised 27.56 GeV HERA positron beam was scattered off a longitudinally polarised pure hydrogen gas target. The average invariant mass of the photon-proton system has a value of <W > = 4.9 GeV, while the average negative squared four-momentum of the virtual photon is <Q(2)> = 1.7 GeV2. The ratio of the present result to the corresponding spin asymmetry in inclusive deep-inelastic scattering is in agreement with an early theoretical prediction based on the generalised vector-meson dominance model. (C) 2001 Published by Elsevier Science B.V.
Metadata last modified: 19 Dec 2024 15:50