The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the proton

Authors
Airapetian, A Akopov, N Akushevich, I Amarian, M Arrington, J Aschenauer, EC Avakian, H Avakian, R Avetissian, A Avetissian, E Bailey, P Bains, B Baumgarten, C Beckmann, M Belostotski, S Bernreuther, S Bianchi, N Bottcher, H Borissov, A Bouwhuis, M Brack, J Brauksiepe, S Braun, B Bruckner, W Brull, A Budz, P Bulten, HJ Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Leo, R De Nardo, L De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Djordjadze, V Duren, M Dvoredsky, A Elbakian, G Ely, J Fantoni, A Fechtchenko, A Ferro-Luzzi, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Garber, Y Garibaldi, F Garutti, E Gavrilov, G Gharibyan, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Gute, A Haeberli, W Hartig, M Hasch, D Heesbeen, D Heinsius, FH Henoch, M Hertenberger, R Hesselink, W Hoffmann-Rothe, P Hofmann, G Holler, Y Holt, RJ Hommez, B Iarygin, G Iodice, M Izotov, A Jackson, HE Jgoun, A Jung, P Kaiser, R Kanesaka, J Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolster, H Korotkov, V Kotik, E Kozlov, V Krivokhijine, VG Kyle, G Lagamba, L Laziev, A Lenisa, P Lindemann, T Lorenzon, W Makins, NCR Martin, JW Marukyan, H Masoli, F McAndrew, M McIlhany, K McKeown, RD Menden, F Metz, A Meyners, N Mikloukho, O Miller, CA Milner, R Mitsyn, V Muccifora, V Mussa, R Nagatisev, A Nappi, E Naryshkin, Y Nass, A Negodaeva, K Nowak, WD O'Neill, TG Openshaw, R Ouyang, J Owen, BR Pate, SF Potashov, S Potterveld, DH Rakness, G Rappoport, V Redwine, R Reggiani, D Reolon, AR Ristinen, R Rith, K Robinson, D Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schafer, A Schill, C Schmidt, F Schnell, G Schuler, KP Schwind, A Seibert, J Seitz, B Shibata, TA Shin, T Shutov, V Simani, C Simon, A Sinram, K Steffens, E Steijger, JJM Stewart, J Stosslein, U Suetsugu, K Sutter, M Tallini, H Taroian, S Terkulov, A Tessarin, S Thomas, E Tipton, B Tytgat, M Urciuoli, GM van den Brand, JFJ van der Steenhoven, G van de Vyver, R van Hunen, JJ Vetterli, MC Vikhrov, V Vincter, MG Visser, J Volk, E Weiskopf, C Wendland, J Wilbert, J Wise, T Yen, S Yoneyama, S Zohrabian, H
Citation
A. Airapetian et al., The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the proton, PHYS LETT B, 494(1-2), 2000, pp. 1-8
Citations number
40
Categorie Soggetti
Physics
Journal title
PHYSICS LETTERS B
ISSN journal
03702693 → ACNP
Volume
494
Issue
1-2
Year of publication
2000
Pages
1 - 8
Database
ISI
SICI code
0370-2693(20001123)494:1-2<1:TQOTGG>2.0.ZU;2-1
Abstract
The dependence on Q(2) (the negative square of the 4-momentum of the exchan ged virtual photon) of the generalised Gerasimov-Drell-Hearn integral for t he proton has been measured in the range 1.2 GeV2 < Q(2) < 12 GeV2 by scatt ering longitudinally polarised positrons on a longitudinally polarised hydr ogen gas target. The contributions of the nucleon-resonance and deep inelas tic regions to this integral have been evaluated separately. The latter has been found to dominate for Q(2) > 3 GeV2, while both contributions are imp ortant at low Q(2). The total integral shows no significant deviation from a 1/Q(2) behaviour in the measured Q(2) range, and thus no sign of large ef fects due to either nucleon-resonance excitations or nonleading twist. (C) 2000 Elsevier Science B.V. All rights reserved.