Evidence for quark-hadron duality in the proton spin asymmetry A1.
Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were scattered off a longitudinally polarized hydrogen target for values of Q2 between 1.2 and 12 GeV2 and values of W2 between 1 and 4 GeV2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable x. This finding implies that the description of A1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2 above 1.6 GeV2.
Airapetian
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A
Yerevan Physics Institute, 375036, Yerevan, Armenia.
Akopov
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Akopov
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Amarian
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Ammosov
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Aschenauer
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Avakian
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Avakian
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Avetissian
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Avetissian
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Bailey
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Baturin
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Baumgarten
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Beckmann
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Belostotski
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Bernreuther
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Bianchi
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Blok
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Böttcher
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Borissov
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Bouhali
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Bouwhuis
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Brack
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Brauksiepe
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Brüll
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Brunn
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Bulten
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Capitani
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Cisbani
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Ciullo
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Court
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Dalpiaz
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De Leo
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De Nardo
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De Sanctis
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Devitsin
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de Witt Huberts
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Di Nezza
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Düren
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Ehrenfried
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Elbakian
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Ellinghaus
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Elschenbroich
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Ely
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Fabbri
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Fantoni
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Fechtchenko
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Felawka
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Filippone
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Fischer
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Fox
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Franz
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Frullani
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Gärber
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Gapienko
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Garibaldi
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Garutti
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Gavrilov
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Gharibyan
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Graw
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Grebeniouk
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Green
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Gute
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Haeberli
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Hafidi
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Hartig
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Hasch
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Heesbeen
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Heinsius
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Henoch
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Hertenberger
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Hesselink
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Hofman
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Holler
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Holt
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Hommez
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Iarygin
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Izotov
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Jackson
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Jung
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Kaiser
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Kinney
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Kisselev
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Kitching
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Königsmann
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Kolster
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Kopytin
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Korotkov
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Kotik
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Kozlov
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Krauss
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Krivokhijine
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Kyle
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Lagamba
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Laziev
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Lenisa
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Liebing
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Lindemann
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Lorenzon
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Maas
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Makins
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Marukyan
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Masoli
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Menden
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Mexner
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Meyners
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Mikloukho
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Miller
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Muccifora
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Nagaitsev
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Nappi
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Naryshkin
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Negodaeva
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Nowak
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Oganessyan
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Orlandi
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Podiatchev
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Potashov
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Potterveld
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Raithel
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Rappoport
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Reggiani
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Reimer
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Reischl
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Reolon
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Rith
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Rostomyan
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Ryckbosch
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Sakemi
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Sanjiev
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Sato
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Savin
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Scarlett
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Schäfer
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Schill
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Schmidt
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Schnell
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Schüler
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Schwind
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Seibert
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Seitz
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Shanidze
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Shibata
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Shutov
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Simani
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Stancari
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Steffens
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Steijger
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Stewart
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Stösslein
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Suetsugu
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Taroian
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Terkulov
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Tessarin
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Thomas
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Tipton
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Tytgat
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Urciuoli
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van den Brand
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van der Steenhoven
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van de Vyver
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Vetterli
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Vikhrov
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Vincter
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Visser
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Volmer
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Weiskopf
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Wendland
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Wilbert
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Wise
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Yen
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Yoneyama
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Zihlmann
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Zohrabian
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