Phys. Rev. C
70,
034606
(2004)
[30 pages]
Dynamics of the quasielastic 16O(e,e′p) reaction at Q2≈0.8 (GeV∕c)2
K. G. Fissum et al. Jefferson Lab Hall A Collaboration
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K. G. Fissum1,2,*, M. Liang3, B. D. Anderson4, K. A. Aniol5, L. Auerbach6, F. T. Baker7, J. Berthot8, W. Bertozzi1, P.-Y. Bertin8, L. Bimbot9, W. U. Boeglin10, E. J. Brash11, V. Breton8, H. Breuer12, E. Burtin13, J. R. Calarco14, L. S. Cardman3, G. D. Cates15,16, C. Cavata13, C. C. Chang12, J.-P. Chen3, E. Cisbani17, D. S. Dale18, C. W. de Jager3, R. De Leo19, A. Deur8,16,3, B. Diederich20, P. Djawotho21, J. Domingo3, J.-E. Ducret13, M. B. Epstein22, L. A. Ewell12, J. M. Finn21, H. Fonvieille8, B. Frois13, S. Frullani17, J. Gao1,23, F. Garibaldi17, A. Gasparian18,24, S. Gilad1, R. Gilman3,25, A. Glamazdin26, C. Glashausser25, J. Gomez3, V. Gorbenko26, T. Gorringe18, F. W. Hersman14, R. Holmes27, M. Holtrop14, N. d’Hose13, C. Howell28, G. M. Huber11, C. E. Hyde-Wright20, M. Iodice17,29, S. Jaminion8, M. K. Jones21,3, K. Joo16,†, C. Jutier8,20, W. Kahl27, S. Kato30, J. J. Kelly12, S. Kerhoas13, M. Khandaker31, M. Khayat4, K. Kino32, W. Korsch18, L. Kramer10, K. S. Kumar15,33, G. Kumbartzki25, G. Laveissière8, A. Leone34, J. J. LeRose3, L. Levchuk26, R. A. Lindgren16, N. Liyanage1,3,16, G. J. Lolos11, R. W. Lourie35,36, R. Madey4,3,24, K. Maeda32, S. Malov25, D. M. Manley4, D. J. Margaziotis22, P. Markowitz10, J. Martino13, J. S. McCarthy16, K. McCormick20,4,25, J. McIntyre25, R. L. J. van der Meer11,3, Z.-E. Meziani6, R. Michaels3, J. Mougey37, S. Nanda3, D. Neyret13, E. A. J. M. Offermann3,36, Z. Papandreou11, C. F. Perdrisat21, R. Perrino34, G. G. Petratos4, S. Platchkov13, R. Pomatsalyuk26, D. L. Prout4, V. A. Punjabi31, T. Pussieux13, G. Quéméner21,8,37, R. D. Ransome25, O. Ravel8, Y. Roblin8,3, R. Roche38,20, D. Rowntree1, G. A. Rutledge21,‡, P. M. Rutt25, A. Saha3, T. Saito32, A. J. Sarty38,39, A. Serdarevic-Offermann11,3, T. P. Smith14, A. Soldi40, P. Sorokin26, P. Souder27, R. Suleiman4,1, J. A. Templon7,§, T. Terasawa32, L. Todor20,**, H. Tsubota32, H. Ueno30, P. E. Ulmer20, G. M. Urciuoli17, P. Vernin13, S. van Verst1, B. Vlahovic40,3, H. Voskanyan41, J. W. Watson4, L. B. Weinstein20, K. Wijesooriya21,42,28, B. Wojtsekhowski3, D. G. Zainea11, V. Zeps18, J. Zhao1, and Z.-L Zhou1 (Jefferson Lab Hall A Collaboration)
1Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
2University of Lund, Box 118, SE-221 00 Lund, Sweden
3Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
4Kent State University, Kent, Ohio 44242, USA
5California State University Los Angeles, Los Angeles, California 90032, USA
6Temple University, Philadelphia, Pennsylvania 19122, USA
7University of Georgia, Athens, Georgia 30602, USA
8IN2P3, F-63177 Aubière, France
9Institut de Physique Nucléaire, F-91406 Orsay, France
10Florida International University, Miami, Florida 33199, USA
11University of Regina, Regina, Saskatchewan, Canada, S4S 0A2
12University of Maryland, College Park, Maryland 20742, USA
13CEA Saclay, F-91191 Gif-sur-Yvette, France
14University of New Hampshire, Durham, New Hampshire 03824, USA
15Princeton University, Princeton, New Jersey 08544, USA
16University of Virginia, Charlottesville, Virginia 22901, USA
17INFN, Sezione Sanitá and Istituto Superiore di Sanitá, Laboratorio di Fisica, I-00161 Rome, Italy
18University of Kentucky, Lexington, Kentucky 40506, USA
19INFN, Sezione di Bari and University of Bari, I-70126 Bari, Italy
20Old Dominion University, Norfolk, Virginia 23529, USA
21College of William and Mary, Williamsburg, Virginia 23187, USA
22California State University, Los Angeles, California 90032, USA
23California Institute of Technology, Pasadena, California 91125, USA
24Hampton University, Hampton, Virginia 23668, USA
25Rutgers, The State University of New Jersey, Piscataway, New Jersey 08554, USA
26Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
27Syracuse University, Syracuse, New York 13244, USA
28Duke University, Durham, North Carolina 27706, USA
29INFN, Sezione di Roma III, I-00146 Rome, Italy
30Yamagata University, Yamagata 990, Japan
31Norfolk State University, Norfolk, Virginia 23504 USA
32Tohoku University, Sendai 980, Japan
33University of Massachusetts, Amherst, Massachusetts 01003, USA
34INFN, Sezione di Lecce, I-73100 Lecce, Italy
35State University of New York at Stony Brook, Stony Brook, New York 11794, USA
36Renaissance Technologies Corporation, Setauket, New York 11733, USA
37Laboratoire de Physique Subatomique et de Cosmologie, F-38026 Grenoble, France
38Florida State University, Tallahassee, Florida 32306, USA
39Saint Mary’s University, Halifax, Nova Scotia, Canada, B3H 3C3
40North Carolina Central University, Durham, North Carolina 27707, USA
41Yerevan Physics Institute, Yerevan 375036, Armenia
42Argonne National Lab, Argonne, Illinois 60439, USA
J. M. Udías and J. R. Vignote
Universidad Complutense de Madrid, E-28040 Madrid, Spain
J. Ryckebusch and D. Debruyne
Ghent University, B-9000 Ghent, Belgium
Received 20 January 2004; published 20 September 2004
The physics program in Hall A at Jefferson Lab commenced in the summer of 1997 with a detailed investigation of the 16O(e,e′p) reaction in quasielastic, constant (q,ω) kinematics at Q2≈0.8 (GeV∕c)2, q≈1 GeV∕c, and ω≈445 MeV. Use of a self-calibrating, self-normalizing, thin-film waterfall target enabled a systematically rigorous measurement. Five-fold differential cross-section data for the removal of protons from the 1p-shell have been obtained for 0<pmiss<350 MeV∕c. Six-fold differential cross-section data for 0<Emiss<120 MeV were obtained for 0<pmiss<340 MeV∕c. These results have been used to extract the ALT asymmetry and the RL, RT, RLT, and RL+TT effective response functions over a large range of Emiss and pmiss. Detailed comparisons of the 1p-shell data with Relativistic Distorted-Wave Impulse Approximation (RDWIA), Relativistic Optical-Model Eikonal Approximation (ROMEA), and Relativistic Multiple-Scattering Glauber Approximation (RMSGA) calculations indicate that two-body currents stemming from meson-exchange currents (MEC) and isobar currents (IC) are not needed to explain the data at this Q2. Further, dynamical relativistic effects are strongly indicated by the observed structure in ALT at pmiss≈300 MeV∕c. For 25<Emiss<50 MeV and pmiss≈50 MeV∕c, proton knockout from the 1s1∕2-state dominates, and ROMEA calculations do an excellent job of explaining the data. However, as pmiss increases, the single-particle behavior of the reaction is increasingly hidden by more complicated processes, and for 280<pmiss<340 MeV∕c, ROMEA calculations together with two-body currents stemming from MEC and IC account for the shape and transverse nature of the data, but only about half the magnitude of the measured cross section. For 50<Emiss<120 MeV and 145<pmiss<340 MeV∕c, (e,e′pN) calculations which include the contributions of central and tensor correlations (two-nucleon correlations) together with MEC and IC (two-nucleon currents) account for only about half of the measured cross section. The kinematic consistency of the 1p-shell normalization factors extracted from these data with respect to all available 16O(e,e′p) data is also examined in detail. Finally, the Q2-dependence of the normalization factors is discussed.
© 2004 American Physical Society
URL:
http://link.aps.org/doi/10.1103/PhysRevC.70.034606
DOI:
10.1103/PhysRevC.70.034606
PACS:
25.30.Fj, 24.70.+s, 27.20.+n
*Corresponding author. Email address: kevin.fissum@nuclear.lu.se †Present address: University of Connecticut, Storrs, Connecticut 06269, USA. ‡Present address: TRIUMF, Vancouver, British Columbia, Canada V6T 2A3. §Present address: NIKHEF, Amsterdam, The Netherlands. **Present address: Carnegie Mellon University, Pittsburgh, Pennsylvania 15217, USA.
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