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arXiv · 0804.3509

Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer

M. M. Dalton·G. S. Adams·A. Ahmidouch·T. Angelescu·J. Arrington·R. Asaturyan·O. K. Baker·N. Benmouna·C. Bertoncini·W. U. Boeglin·P. E. Bosted·H. Breuer·M. E. Christy·S. H. Connell·Y. Cui·S. Danagoulian·D. Day·T. Dodario·J. A. Dunne·D. Dutta·N. El Khayari·R. Ent·H. C. Fenker·V. V. Frolov·L. Gan·D. Gaskell·K. Hafidi·W. Hinton·R. J. Holt·T. Horn·G. M. Huber·E. Hungerford·X. Jiang·M. K. Jones·K. Joo·N. Kalantarians·J. J. Kelly·C. E. Keppel·V. Kubarovsky·Y. Li·Y. Liang·S. Malace·P. Markowitz·P. McKee·D. G. Meekins·H. Mkrtchyan·B. Moziak·T. Navasardyan·G. Niculescu·I. Niculescu·A. K. Opper·T. Ostapenko·P. E. Reimer·J. Reinhold·J. Roche·S. E. Rock·E. Schulte·E. Segbefia·C. Smith·G. R. Smith·P. Stoler·V. Tadevosyan·L. Tang·V. Tvaskis·M. Ungaro·A. Uzzle·S. Vidakovic·A. Villano·W. F. Vulcan·M. Wang·G. Warren·F. R. Wesselmann·B. Wojtsekhowski·S. A. Wood·C. Xu·L. Yuan·X. Zheng·H. Zhu
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Abstract

The differential cross-section for the process p(e,e'p)eta has been measured at Q2 ~ 5.7 and 7.0 (GeV/c)2 for centre-of-mass energies from threshold to 1.8 GeV, encompassing the S11(1535) resonance, which dominates the channel. This is the highest momentum transfer measurement of this exclusive process to date. The helicity-conserving transition amplitude A_1/2, for the production of the S11(1535) resonance, is extracted from the data. Within the limited Q2 now measured, this quantity appears to begin scaling as 1/Q3 - a predicted, but not definitive, signal of the dominance of perturbative QCD, at Q2 ~ 5 (GeV/c)2.

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M. M. Dalton, G. S. Adams, A. Ahmidouch, T. Angelescu, J. Arrington, R. Asaturyan, O. K. Baker, N. Benmouna, C. Bertoncini, W. U. Boeglin, P. E. Bosted, H. Breuer, M. E. Christy, S. H. Connell, Y. Cui, S. Danagoulian, D. Day, T. Dodario, J. A. Dunne, D. Dutta, N. El Khayari, R. Ent, H. C. Fenker, V. V. Frolov, L. Gan, D. Gaskell, K. Hafidi, W. Hinton, R. J. Holt, T. Horn, G. M. Huber, E. Hungerford, X. Jiang, M. K. Jones, K. Joo, N. Kalantarians, J. J. Kelly, C. E. Keppel, V. Kubarovsky, Y. Li, Y. Liang, S. Malace, P. Markowitz, P. McKee, D. G. Meekins, H. Mkrtchyan, B. Moziak, T. Navasardyan, G. Niculescu, I. Niculescu, A. K. Opper, T. Ostapenko, P. E. Reimer, J. Reinhold, J. Roche, S. E. Rock, E. Schulte, E. Segbefia, C. Smith, G. R. Smith, P. Stoler, V. Tadevosyan, L. Tang, V. Tvaskis, M. Ungaro, A. Uzzle, S. Vidakovic, A. Villano, W. F. Vulcan, M. Wang, G. Warren, F. R. Wesselmann, B. Wojtsekhowski, S. A. Wood, C. Xu, L. Yuan, X. Zheng, H. Zhu. 2009-06-07. Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer. https://doi.org/10.1103/physrevc.80.015205

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