Single-transverse-spin asymmetries of identified charged hadrons in polarized pp collisions at sqrt[s]=62.4 GeV.
The first measurements of xF-dependent single-spin asymmetries of identified charged hadrons, pi+/-, K+/-, and protons, from transversely polarized proton-proton collisions at 62.4 GeV at RHIC are presented. Large asymmetries are seen in the pion and kaon channels. The asymmetries in inclusive pi+ production, AN(pi+), increase with xF from 0 to approximately 0.25 and AN(pi-) decrease from 0 to approximately -0.4. Observed asymmetries for K- unexpectedly show positive values similar to those for K+, increasing with xF, whereas proton asymmetries are consistent with zero over the measured kinematic range. Comparisons of the data with predictions of QCD-based models are presented.
Arsene
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I
Department of Physics, University of Oslo, Oslo, Norway.
Bearden
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Beavis
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Bekele
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Besliu
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Budick
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Bøggild
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Chasman
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Dalsgaard
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Debbe
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Fox
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Gaardhøje
J J
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Hagel
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Jipa
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Johnson
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Karabowicz
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Katryńska
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Kim
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Larsen
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Lee
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Løvhøiden
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Majka
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Murray
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Nygaard
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Natowitz
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Nielsen
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Pal
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Qviler
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Ristea
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Röhrich
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Sanders
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Staszel
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Tveter
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Videbaek
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Yang
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Wada
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