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Posik M, Flay D, Parno DS, Allada K, Armstrong W, Averett T, Benmokhtar F, Bertozzi W, Camsonne A, Canan M, Cates GD, Chen C, Chen JP, Choi S, Chudakov E, Cusanno F, Dalton MM, Deconinck W, de Jager CW, Deng X, Deur A, Dutta C, El Fassi L, Franklin GB, Friend M, Gao H, Garibaldi F, Gilad S, Gilman R, Glamazdin O, Golge S, Gomez J, Guo L, Hansen O, Higinbotham DW, Holmstrom T, Huang J, Hyde C, Ibrahim HF, Jiang X, Jin G, Katich J, Kelleher A, Kolarkar A, Korsch W, Kumbartzki G, LeRose JJ, Lindgren R, Liyanage N, Long E, Lukhanin A, Mamyan V, McNulty D, Meziani ZE, Michaels R, Mihovilovič M, Moffit B, Muangma N, Nanda S, Narayan A, Nelyubin V, Norum B, Oh Y, Peng JC, Qian X, Qiang Y, Rakhman A, Riordan S, Saha A, Sawatzky B, Shabestari MH, Shahinyan A, Širca S, Solvignon P, Subedi R, Sulkosky V, Tobias WA, Troth W, Wang D, Wang Y, Wojtsekhowski B, Yan X, Yao H, Ye Y, Ye Z, Yuan L, Zhan X, Zhang Y, Zhang YW, Zhao B, Zheng X. Precision measurement of the neutron twist-3 matrix element d(2)(n): probing color forces. Phys Rev Lett 2014; 113:022002. [PMID: 25062166 DOI: 10.1103/physrevlett.113.022002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Indexed: 06/03/2023]
Abstract
Double-spin asymmetries and absolute cross sections were measured at large Bjorken x (0.25≤x≤0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized (3)He target. In this dedicated experiment, the spin structure function g(2)((3)He) was determined with precision at large x, and the neutron twist-3 matrix element d(2)(n) was measured at ⟨Q(2)⟩ of 3.21 and 4.32 GeV(2)/c(2), with an absolute precision of about 10(-5). Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at ⟨Q(2)⟩=5 GeV(2)/c(2). Combining d(2)(n) and a newly extracted twist-4 matrix element f(2)(n), the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 30 MeV/fm in magnitude.
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Affiliation(s)
- M Posik
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D Flay
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D S Parno
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA and Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98195, USA
| | - K Allada
- University of Kentucky, Lexington, Kentucky 40506, USA
| | - W Armstrong
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - T Averett
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - F Benmokhtar
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA and Duquesne University, Pittsburgh, Pennsylvania 15282, USA
| | - W Bertozzi
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Canan
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - G D Cates
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - C Chen
- Hampton University, Hampton, Virginia 23187, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Choi
- Seoul National University, Seoul 151-742, South Korea
| | - E Chudakov
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Cusanno
- INFN, Sezione di Roma, I-00161 Rome, Italy and Istituto Superiore di Sanità, I-00161 Rome, Italy
| | - M M Dalton
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - W Deconinck
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C W de Jager
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Deng
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - A Deur
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Dutta
- University of Kentucky, Lexington, Kentucky 40506, USA
| | - L El Fassi
- Old Dominion University, Norfolk, Virginia 23529, USA and Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA
| | - G B Franklin
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - M Friend
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - H Gao
- Duke University, Durham, North Carolina 27708, USA
| | | | - S Gilad
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R Gilman
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA
| | - O Glamazdin
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - S Golge
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - J Gomez
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - L Guo
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D W Higinbotham
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Holmstrom
- Longwood University, Farmville, Virginia 23909, USA
| | - J Huang
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Hyde
- Old Dominion University, Norfolk, Virginia 23529, USA and Université Blaise Pascal/IN2P3, F-63177 Aubière, France
| | | | - X Jiang
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA and Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - G Jin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J Katich
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - A Kelleher
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - A Kolarkar
- University of Kentucky, Lexington, Kentucky 40506, USA
| | - W Korsch
- University of Kentucky, Lexington, Kentucky 40506, USA
| | - G Kumbartzki
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA
| | - J J LeRose
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Lindgren
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - N Liyanage
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - E Long
- Kent State University, Kent, Ohio 44242, USA
| | - A Lukhanin
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - V Mamyan
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - D McNulty
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Z-E Meziani
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - B Moffit
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N Muangma
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S Nanda
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Narayan
- Mississippi State University, Mississippi 39762, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - B Norum
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - Y Oh
- Seoul National University, Seoul 151-742, South Korea
| | - J C Peng
- University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - X Qian
- Duke University, Durham, North Carolina 27708, USA and Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125, USA
| | - Y Qiang
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Duke University, Durham, North Carolina 27708, USA
| | - A Rakhman
- Syracuse University, Syracuse, New York 13244, USA
| | - S Riordan
- University of Virginia, Charlottesville, Virginia 22904, USA and University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - A Saha
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Sawatzky
- Temple University, Philadelphia, Pennsylvania 19122, USA and Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M H Shabestari
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - A Shahinyan
- Yerevan Physics Institute, Yerevan 375036, Armenia
| | - S Širca
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia and University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - P Solvignon
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Argonne National Lab, Argonne, Illinois 60439, USA
| | - R Subedi
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - V Sulkosky
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - W A Tobias
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - W Troth
- Longwood University, Farmville, Virginia 23909, USA
| | - D Wang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - Y Wang
- University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - B Wojtsekhowski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Yan
- University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - H Yao
- Temple University, Philadelphia, Pennsylvania 19122, USA and College of William and Mary, Williamsburg, Virginia 23187, USA
| | - Y Ye
- University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Z Ye
- Hampton University, Hampton, Virginia 23187, USA
| | - L Yuan
- Hampton University, Hampton, Virginia 23187, USA
| | - X Zhan
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Y Zhang
- Lanzhou University, Lanzhou 730000, Gansu, People's Republic of China
| | - Y-W Zhang
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855, USA and Lanzhou University, Lanzhou 730000, Gansu, People's Republic of China
| | - B Zhao
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - X Zheng
- University of Virginia, Charlottesville, Virginia 22904, USA
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Abrahamyan S, Ahmed Z, Albataineh H, Aniol K, Armstrong DS, Armstrong W, Averett T, Babineau B, Barbieri A, Bellini V, Beminiwattha R, Benesch J, Benmokhtar F, Bielarski T, Boeglin W, Camsonne A, Canan M, Carter P, Cates GD, Chen C, Chen JP, Hen O, Cusanno F, Dalton MM, De Leo R, de Jager K, Deconinck W, Decowski P, Deng X, Deur A, Dutta D, Etile A, Flay D, Franklin GB, Friend M, Frullani S, Fuchey E, Garibaldi F, Gasser E, Gilman R, Giusa A, Glamazdin A, Gomez J, Grames J, Gu C, Hansen O, Hansknecht J, Higinbotham DW, Holmes RS, Holmstrom T, Horowitz CJ, Hoskins J, Huang J, Hyde CE, Itard F, Jen CM, Jensen E, Jin G, Johnston S, Kelleher A, Kliakhandler K, King PM, Kowalski S, Kumar KS, Leacock J, Leckey J, Lee JH, LeRose JJ, Lindgren R, Liyanage N, Lubinsky N, Mammei J, Mammoliti F, Margaziotis DJ, Markowitz P, McCreary A, McNulty D, Mercado L, Meziani ZE, Michaels RW, Mihovilovic M, Muangma N, Muñoz-Camacho C, Nanda S, Nelyubin V, Nuruzzaman N, Oh Y, Palmer A, Parno D, Paschke KD, Phillips SK, Poelker B, Pomatsalyuk R, Posik M, Puckett AJR, Quinn B, Rakhman A, Reimer PE, Riordan S, Rogan P, Ron G, Russo G, Saenboonruang K, Saha A, Sawatzky B, Shahinyan A, Silwal R, Sirca S, Slifer K, Solvignon P, Souder PA, Sperduto ML, Subedi R, Suleiman R, Sulkosky V, Sutera CM, Tobias WA, Troth W, Urciuoli GM, Waidyawansa B, Wang D, Wexler J, Wilson R, Wojtsekhowski B, Yan X, Yao H, Ye Y, Ye Z, Yim V, Zana L, Zhan X, Zhang J, Zhang Y, Zheng X, Zhu P. Measurement of the neutron radius of 208Pb through parity violation in electron scattering. Phys Rev Lett 2012; 108:112502. [PMID: 22540469 DOI: 10.1103/physrevlett.108.112502] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Indexed: 05/31/2023]
Abstract
We report the first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb. A(PV) is sensitive to the radius of the neutron distribution (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.
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