Measurement of the generalized polarizabilities of the proton in virtual Compton scattering at Q2=0.92 and 1.76 GeV2

G Laveissière; L Todor; N Degrande; S Jaminion; C Jutier; R Di Salvo; L Van Hoorebeke; L C Alexa; B D Anderson; K A Aniol; K Arundell; G Audit; L Auerbach; F T Baker; M Baylac; J Berthot; P Y Bertin; W Bertozzi; L Bimbot; W U Boeglin; E J Brash; V Breton; H Breuer; E Burtin; J R Calarco; L S Cardman; C Cavata; C-C Chang; J-P Chen; E Chudakov; E Cisbani; D S Dale; C W de Jager; R De Leo; A Deur; N d'Hose; G E Dodge; J J Domingo; L Elouadrhiri; M B Epstein; L A Ewell; J M Finn; K G Fissum; H Fonvieille; G Fournier; B Frois; S Frullani; C Furget; H Gao; J Gao; F Garibaldi; A Gasparian; S Gilad; R Gilman; A Glamazdin; C Glashausser; J Gomez; V Gorbenko; P Grenier; P A M Guichon; J O Hansen; R Holmes; M Holtrop; C Howell; G M Huber; C E Hyde-Wright; S Incerti; M Iodice; J Jardillier; M K Jones; W Kahl; S Kato; A T Katramatou; J J Kelly; S Kerhoas; A Ketikyan; M Khayat; K Kino; S Kox; L H Kramer; K S Kumar; G Kumbartzki; M Kuss; A Leone; J J LeRose; M Liang; R A Lindgren; N Liyanage; G J Lolos; R W Lourie; R Madey; K Maeda; S Malov; D M Manley; C Marchand; D Marchand; D J Margaziotis; P Markowitz; J Marroncle; J Martino; K McCormick; J McIntyre; S Mehrabyan; F Merchez; Z E Meziani; R Michaels; G W Miller; J Y Mougey; S K Nanda; D Neyret; E A J M Offermann; Z Papandreou; B Pasquini; C F Perdrisat; R Perrino; G G Petratos; S Platchkov; R Pomatsalyuk; D L Prout; V A Punjabi; T Pussieux; G Quémenér; R D Ransome; O Ravel; J S Real; F Renard; Y Roblin; D Rowntree; G Rutledge; P M Rutt; A Saha; T Saito; A J Sarty; A Serdarevic; T Smith; G Smirnov; K Soldi; P Sorokin; P A Souder; R Suleiman; J A Templon; T Terasawa; R Tieulent; E Tomasi-Gustaffson; H Tsubota; H Ueno; P E Ulmer; G M Urciuoli; M Vanderhaeghen; R Van De Vyver; R L J Van der Meer; P Vernin; B Vlahovic; H Voskanyan; E Voutier; J W Watson; L B Weinstein; K Wijesooriya; R Wilson; B B Wojtsekhowski; D G Zainea; W-M Zhang; J Zhao; Z-L Zhou; Jefferson Lab Hall A Collaboration

doi:10.1103/PhysRevLett.93.122001

Measurement of the generalized polarizabilities of the proton in virtual Compton scattering at Q2=0.92 and 1.76 GeV2

Phys Rev Lett. 2004 Sep 17;93(12):122001. doi: 10.1103/PhysRevLett.93.122001. Epub 2004 Sep 14.

Authors

G Laveissière¹, L Todor, N Degrande, S Jaminion, C Jutier, R Di Salvo, L Van Hoorebeke, L C Alexa, B D Anderson, K A Aniol, K Arundell, G Audit, L Auerbach, F T Baker, M Baylac, J Berthot, P Y Bertin, W Bertozzi, L Bimbot, W U Boeglin, E J Brash, V Breton, H Breuer, E Burtin, J R Calarco, L S Cardman, C Cavata, C-C Chang, J-P Chen, E Chudakov, E Cisbani, D S Dale, C W de Jager, R De Leo, A Deur, N d'Hose, G E Dodge, J J Domingo, L Elouadrhiri, M B Epstein, L A Ewell, J M Finn, K G Fissum, H Fonvieille, G Fournier, B Frois, S Frullani, C Furget, H Gao, J Gao, F Garibaldi, A Gasparian, S Gilad, R Gilman, A Glamazdin, C Glashausser, J Gomez, V Gorbenko, P Grenier, P A M Guichon, J O Hansen, R Holmes, M Holtrop, C Howell, G M Huber, C E Hyde-Wright, S Incerti, M Iodice, J Jardillier, M K Jones, W Kahl, S Kato, A T Katramatou, J J Kelly, S Kerhoas, A Ketikyan, M Khayat, K Kino, S Kox, L H Kramer, K S Kumar, G Kumbartzki, M Kuss, A Leone, J J LeRose, M Liang, R A Lindgren, N Liyanage, G J Lolos, R W Lourie, R Madey, K Maeda, S Malov, D M Manley, C Marchand, D Marchand, D J Margaziotis, P Markowitz, J Marroncle, J Martino, K McCormick, J McIntyre, S Mehrabyan, F Merchez, Z E Meziani, R Michaels, G W Miller, J Y Mougey, S K Nanda, D Neyret, E A J M Offermann, Z Papandreou, B Pasquini, C F Perdrisat, R Perrino, G G Petratos, S Platchkov, R Pomatsalyuk, D L Prout, V A Punjabi, T Pussieux, G Quémenér, R D Ransome, O Ravel, J S Real, F Renard, Y Roblin, D Rowntree, G Rutledge, P M Rutt, A Saha, T Saito, A J Sarty, A Serdarevic, T Smith, G Smirnov, K Soldi, P Sorokin, P A Souder, R Suleiman, J A Templon, T Terasawa, R Tieulent, E Tomasi-Gustaffson, H Tsubota, H Ueno, P E Ulmer, G M Urciuoli, M Vanderhaeghen, R Van De Vyver, R L J Van der Meer, P Vernin, B Vlahovic, H Voskanyan, E Voutier, J W Watson, L B Weinstein, K Wijesooriya, R Wilson, B B Wojtsekhowski, D G Zainea, W-M Zhang, J Zhao, Z-L Zhou; Jefferson Lab Hall A Collaboration

Affiliation

¹ Université Blaise Pascal/IN2P3, F-63177 Aubière, France.

PMID: 15447252
DOI: 10.1103/PhysRevLett.93.122001

Abstract

We report a virtual Compton scattering study of the proton at low c.m. energies. We have determined the structure functions P(LL)-P(TT)/epsilon and P(LT), and the electric and magnetic generalized polarizabilities (GPs) alpha(E)(Q2) and beta(M)(Q2) at momentum transfer Q(2)=0.92 and 1.76 GeV2. The electric GP shows a strong falloff with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a falloff; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from piN intermediate states.