Phys. Rev. Lett.
98,
032301
(2007)
[5 pages]
Precision Measurements of the Nucleon Strange Form Factors at Q2∼0.1 GeV2
A. Acha et al. HAPPEX Collaboration
Show All Authors/Affiliations
Hide All Authors/Affiliations
A. Acha1, K. A. Aniol2, D. S. Armstrong3, J. Arrington4, T. Averett3, S. L. Bailey3, J. Barber5, A. Beck6, H. Benaoum7, J. Benesch8, P. Y. Bertin9, P. Bosted8, F. Butaru10, E. Burtin11, G. D. Cates12, Y.-C. Chao8, J.-P. Chen8, E. Chudakov8, E. Cisbani13, B. Craver12, F. Cusanno13, R. De Leo14, P. Decowski15, A. Deur8, R. J. Feuerbach8, J. M. Finn3, S. Frullani13, S. A. Fuchs3, K. Fuoti5, R. Gilman16,8, L. E. Glesener3, K. Grimm3, J. M. Grames8, J. O. Hansen8, J. Hansknecht8, D. W. Higinbotham8, R. Holmes7, T. Holmstrom3, H. Ibrahim17, C. W. de Jager8, X. Jiang16, J. Katich3, L. J. Kaufman5, A. Kelleher3, P. M. King18, A. Kolarkar19, S. Kowalski6, E. Kuchina16, K. S. Kumar5, L. Lagamba14, P. LaViolette5, J. LeRose8, R. A. Lindgren12, D. Lhuillier11, N. Liyanage12, D. J. Margaziotis2, P. Markowitz1, D. G. Meekins8, Z.-E. Meziani10, R. Michaels8, B. Moffit3, S. Nanda8, V. Nelyubin12,20, K. Otis5, K. D. Paschke5, S. K. Phillips3, M. Poelker8, R. Pomatsalyuk21, M. Potokar22, Y. Prok12, A. Puckett6, X. Qian23, Y. Qiang6, B. Reitz8, J. Roche8, A. Saha8, B. Sawatzky10, J. Singh12, K. Slifer10, S. Sirca6, R. Snyder12, P. Solvignon10, P. A. Souder7, M. L. Stutzman8, R. Subedi24, R. Suleiman6, V. Sulkosky3, W. A. Tobias12, P. E. Ulmer17, G. M. Urciuoli13, K. Wang12, A. Whitbeck8, R. Wilson25, B. Wojtsekhowski8, H. Yao10, Y. Ye26, X. Zhan6, X. Zheng6,4, S. Zhou27, and V. Ziskin6 (HAPPEX Collaboration)
1Florida International University, Miami, Florida 33199, USA
2California State University, Los Angeles, Los Angeles, California 90032, USA
3College of William and Mary, Williamsburg, Virginia 23187, USA
4Argonne National Laboratory, Argonne, Illinois 60439, USA
5University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
6Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
7Syracuse University, Syracuse, New York 13244, USA
8Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
9Université Blaise Pascal/CNRS-IN2P3, F-63177 Aubière, France
10Temple University, Philadelphia, Pennsylvania 19122, USA
11CEA Saclay, DAPNIA/SPhN, F-91191 Gif-sur-Yvette, France
12University of Virginia, Charlottesville, Virginia 22904, USA
13Istituto Nazionale di Fisica Nucleare, Sezione Sanità, 00161 Roma, Italy
14Istituto Nazionale di Fisica Nucleare, Sezione di Bari and University of Bari, I-70126 Bari, Italy
15Smith College, Northampton, Massachusetts 01063, USA
16Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA
17Old Dominion University, Norfolk, Virginia 23529, USA
18University of Illinois, Urbana, Illinois 61801, USA
19University of Kentucky, Lexington, Kentucky 40506, USA
20St. Petersburg Nuclear Physics Institute of Russian Academy of Science, Gatchina, 188350, Russia
21Kharkov Institute of Physics and Technology, Kharkov 310108, Ukraine
22Jozef Stefan Institute, 1000 Ljubljana, Slovenia
23Duke University, TUNL, Durham, North Carolina 27706, USA
24Kent State University, Kent, Ohio 44242, USA
25Harvard University, Cambridge, Massachusetts 02138, USA
26University of Science and Technology of China, Heifei, Anhui 230026, China
27China Institute of Atomic Energy, Beijing 102413, China
Received 6 September 2006; published 18 January 2007
We report new measurements of the parity-violating asymmetry APV in elastic scattering of 3 GeV electrons off hydrogen and 4He targets with ⟨θlab⟩≈6.0°. The 4He result is APV=(+6.40±0.23(stat)±0.12(syst))×10-6. The hydrogen result is APV=(-1.58±0.12(stat)±0.04(syst))×10-6. These results significantly improve constraints on the electric and magnetic strange form factors GEs and GMs. We extract GEs=0.002±0.014±0.007 at ⟨Q2⟩=0.077 GeV2, and GEs+0.09GMs=0.007±0.011±0.006 at ⟨Q2⟩=0.109 GeV2, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions.
© 2007 The American Physical Society
URL:
http://link.aps.org/doi/10.1103/PhysRevLett.98.032301
DOI:
10.1103/PhysRevLett.98.032301
PACS:
25.30.Bf, 11.30.Er, 13.40.Gp, 13.60.Fz
|
|
