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Chirapatpimol K, Shabestari MH, Lindgren RA, Smith LC, Annand JRM, Higinbotham DW, Moffit B, Nelyubin V, Norum BE, Allada K, Aniol K, Ardashev K, Armstrong DS, Arndt RA, Benmokhtar F, Bernstein AM, Bertozzi W, Briscoe WJ, Bimbot L, Camsonne A, Chen JP, Choi S, Chudakov E, Cisbani E, Cusanno F, Dalton MM, Dutta C, Egiyan K, Fernàndez-Ramìrez C, Feuerbach R, Fissum KG, Frullani S, Garibaldi F, Gayou O, Gilman R, Gilad S, Goity J, Gomez J, Hahn B, Hamilton D, Hansen JO, Huang J, Igarashi R, Ireland D, de Jager CW, Jin X, Jiang X, Jinasundera T, Kellie J, Keppel CE, Kolb N, LeRose J, Liyanage N, Livingston K, McNulty D, Mercado L, Michaels R, Mihovilovič M, Qian S, Qian X, Mailyan S, Mamyan V, Marrone S, Monaghan P, Nanda S, Perdrisat CF, Piasetzky E, Protopopescu D, Punjabi V, Qiang Y, Rachek IA, Rakhman A, Riordan S, Ron G, Rosner G, Saha A, Sawatzky B, Shahinyan A, Širca S, Sparveris N, Subedi RR, Suleiman R, Strakovsky I, Sulkosky V, Moinelo J, Voskanyan H, Wang K, Wang Y, Watson J, Watts D, Wojtsekhowski B, Workman RL, Yao H, Zhan X, Zhang Y. Precision Measurement of the p(e,e^{'}p)π^{0} Reaction at Threshold. Phys Rev Lett 2015; 114:192503. [PMID: 26024167 DOI: 10.1103/physrevlett.114.192503] [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: 02/19/2015] [Indexed: 06/04/2023]
Abstract
New results are reported from a measurement of π^{0} electroproduction near threshold using the p(e,e^{'}p)π^{0} reaction. The experiment was designed to determine precisely the energy dependence of s- and p-wave electromagnetic multipoles as a stringent test of the predictions of chiral perturbation theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the ϕ_{π}^{*} and θ_{π}^{*} angles in the pπ^{0} center of mass was obtained for invariant energies above threshold from 0.5 up to 15 MeV. The 4-momentum transfer Q^{2} coverage ranges from 0.05 to 0.155 (GeV/c)^{2} in fine steps. A simple phenomenological analysis of our data shows strong disagreement with p-wave predictions from ChPT for Q^{2}>0.07 (GeV/c)^{2}, while the s-wave predictions are in reasonable agreement.
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Affiliation(s)
- K Chirapatpimol
- University of Virginia, Charlottesville, Virginia 22904, USA
- Chiang Mai University, Chiang Mai, Thailand 50200
| | - M H Shabestari
- University of Virginia, Charlottesville, Virginia 22904, USA
- Mississipi State University, Starkville, Mississippi 39762, USA
| | - R A Lindgren
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - L C Smith
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J R M Annand
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - D W Higinbotham
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Moffit
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - B E Norum
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - K Allada
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - K Aniol
- California State University, Los Angeles, Los Angeles, California 90032, USA
| | - K Ardashev
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - D S Armstrong
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - R A Arndt
- The George Washington University, Washington, D.C. 20052, USA
| | - F Benmokhtar
- Duquesne University, Pittsburgh, Pennsylvania 15282, USA
| | - A M Bernstein
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - W Bertozzi
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - W J Briscoe
- The George Washington University, Washington, D.C. 20052, USA
| | - L Bimbot
- Institut de Physique Nucleaire, F-91406 Orsay Cedex, France
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Choi
- Seoul National University, Seoul 151-747, Korea
| | - E Chudakov
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - E Cisbani
- Istituto Nazionale di Fisica Nucleare, Sezione Sanità, I-00161 Rome, Italy
| | - F Cusanno
- Istituto Nazionale di Fisica Nucleare, Sezione Sanità, I-00161 Rome, Italy
| | - M M Dalton
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Dutta
- University of Kentucky, Lexington, Kentucky 40506, USA
| | - K Egiyan
- Yerevan Physics Institute, Yerevan, 0036 Armenia
| | - C Fernàndez-Ramìrez
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Feuerbach
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K G Fissum
- University of Lund, Box 118, SE-221 00 Lund, Sweden
| | - S Frullani
- Istituto Nazionale di Fisica Nucleare, Sezione Sanità, I-00161 Rome, Italy
| | - F Garibaldi
- Istituto Nazionale di Fisica Nucleare, Sezione Sanità, I-00161 Rome, Italy
| | - O Gayou
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R Gilman
- Rutgers University, New Brunswick, New Jersey 08903, USA
| | - S Gilad
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Goity
- Hampton University, Hampton, Virginia 23668, USA
| | - J Gomez
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Hahn
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - D Hamilton
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - J-O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Huang
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R Igarashi
- University of Saskatchewan, Saskatoon, Canada S7N 0W0
| | - D Ireland
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - C W de Jager
- University of Virginia, Charlottesville, Virginia 22904, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Jin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - X Jiang
- Rutgers University, New Brunswick, New Jersey 08903, USA
| | - T Jinasundera
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J Kellie
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - C E Keppel
- Hampton University, Hampton, Virginia 23668, USA
| | - N Kolb
- University of Saskatchewan, Saskatoon, Canada S7N 0W0
| | - J LeRose
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N Liyanage
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - K Livingston
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - D McNulty
- University of Massachusetts, Amherst, Massachusetts 01003, USA
- Idaho State University, Pocatello, Idaho, 83209, USA
| | - L Mercado
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - S Qian
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - X Qian
- Duke University, Durham, North Carolina 27708, USA
| | - S Mailyan
- Yerevan Physics Institute, Yerevan, 0036 Armenia
| | - V Mamyan
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S Marrone
- Istituto Nazionale di Fisica Nucleare, Sezione Sanità, I-00161 Rome, Italy
| | - P Monaghan
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S Nanda
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C F Perdrisat
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | | | - D Protopopescu
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - Y Qiang
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - I A Rachek
- Budker Institute, 630090 Novosibirsk, Russia
| | - A Rakhman
- Syracuse University, Syracuse, New York 13244, USA
| | - S Riordan
- University of Massachusetts, Amherst, Massachusetts 01003, USA
- Stony Brook University, Stony Brook, New York 11794, USA
| | - G Ron
- Lawrence Berkeley National Lab, Berkeley, California 94720, USA
- Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem, Israel 91904
| | - G Rosner
- University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
| | - A Saha
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Temple University, Philadelphia, PA 19122 USA
| | - A Shahinyan
- Yerevan Physics Institute, Yerevan, 0036 Armenia
| | - S Širca
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
- University of Ljubljana, 1000 Ljubljana, Slovenia
| | - N Sparveris
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Temple University, Philadelphia, PA 19122 USA
| | - R R Subedi
- Kent State University, Kent, Ohio 44242, USA
| | - R Suleiman
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - I Strakovsky
- The George Washington University, Washington, D.C. 20052, USA
| | - V Sulkosky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Moinelo
- Universidad Complutense de Madrid, Madrid 98040, Spain
| | - H Voskanyan
- Yerevan Physics Institute, Yerevan, 0036 Armenia
| | - K Wang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - Y Wang
- Rutgers University, New Brunswick, New Jersey 08903, USA
| | - J Watson
- Kent State University, Kent, Ohio 44242, USA
| | - D Watts
- University of Edinburgh, Edinburgh, EH8 9YL Scotland, United Kingdom
| | - B Wojtsekhowski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R L Workman
- The George Washington University, Washington, D.C. 20052, USA
| | - H Yao
- Temple University, Philadelphia, PA 19122 USA
| | - X Zhan
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Y Zhang
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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