1
|
Akimov D, An P, Awe C, Barbeau PS, Becker B, Belov V, Bernardi I, Blackston MA, Bock C, Bolozdynya A, Browning J, Cabrera-Palmer B, Chernyak D, Conley E, Daughhetee J, Detwiler J, Ding K, Durand MR, Efremenko Y, Elliott SR, Fabris L, Febbraro M, Gallo Rosso A, Galindo-Uribarri A, Green MP, Heath MR, Hedges S, Hoang D, Hughes M, Johnson T, Khromov A, Konovalov A, Kozlova E, Kumpan A, Li L, Link JM, Liu J, Mann K, Markoff DM, Mastroberti J, Mueller PE, Newby J, Parno DS, Penttila SI, Pershey D, Rapp R, Raybern J, Razuvaeva O, Reyna D, Rich GC, Ross J, Rudik D, Runge J, Salvat DJ, Salyapongse AM, Sander J, Scholberg K, Shakirov A, Simakov G, Sinev G, Snow WM, Sosnovtsev V, Suh B, Tayloe R, Tellez-Giron-Flores K, Tolstukhin I, Ujah E, Vanderwerp J, Varner RL, Virtue CJ, Visser G, Wongjirad T, Yen YR, Yoo J, Yu CH, Zettlemoyer J. First Probe of Sub-GeV Dark Matter beyond the Cosmological Expectation with the COHERENT CsI Detector at the SNS. Phys Rev Lett 2023; 130:051803. [PMID: 36800477 DOI: 10.1103/physrevlett.130.051803] [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: 09/23/2022] [Accepted: 11/28/2022] [Indexed: 06/18/2023]
Abstract
The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence for dark matter is found and we thus place limits on allowed parameter space. With this low-threshold detector, we are sensitive to coherent elastic scattering between dark matter and nuclei. The cross section for this process is orders of magnitude higher than for other processes historically used for accelerator-based direct-detection searches so that our small, 14.6 kg detector significantly improves on past constraints. At peak sensitivity, we reject the flux consistent with the cosmologically observed dark-matter concentration for all coupling constants α_{D}<0.64, assuming a scalar dark-matter particle. We also calculate the sensitivity of future COHERENT detectors to dark-matter signals which will ambitiously test multiple dark-matter spin scenarios.
Collapse
Affiliation(s)
- D Akimov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - P An
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - C Awe
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - P S Barbeau
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - B Becker
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - V Belov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- National Research Center "Kurchatov Institute," Moscow 123182, Russian Federation
| | - I Bernardi
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - M A Blackston
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C Bock
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - A Bolozdynya
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - J Browning
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | | | - D Chernyak
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - E Conley
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - J Daughhetee
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Detwiler
- Center for Experimental Nuclear Physics and Astrophysics and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - K Ding
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - M R Durand
- Center for Experimental Nuclear Physics and Astrophysics and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Y Efremenko
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S R Elliott
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - L Fabris
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M Febbraro
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Gallo Rosso
- Department of Physics, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - A Galindo-Uribarri
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M P Green
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - M R Heath
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S Hedges
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Lawrence Livermore National Laboratory, Livermore, California, 94550, USA
| | - D Hoang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - M Hughes
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - T Johnson
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - A Khromov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - A Konovalov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- National Research Center "Kurchatov Institute," Moscow 123182, Russian Federation
| | - E Kozlova
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- National Research Center "Kurchatov Institute," Moscow 123182, Russian Federation
| | - A Kumpan
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - L Li
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - J M Link
- Center for Neutrino Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - J Liu
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - K Mann
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - D M Markoff
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Mathematics and Physics, North Carolina Central University, Durham, North Carolina 27707, USA
| | - J Mastroberti
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - P E Mueller
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Newby
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D S Parno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S I Penttila
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D Pershey
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - R Rapp
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - J Raybern
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - O Razuvaeva
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- National Research Center "Kurchatov Institute," Moscow 123182, Russian Federation
| | - D Reyna
- Sandia National Laboratories, Livermore, California 94550, USA
| | - G C Rich
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - J Ross
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Mathematics and Physics, North Carolina Central University, Durham, North Carolina 27707, USA
| | - D Rudik
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - J Runge
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - D J Salvat
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - A M Salyapongse
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - J Sander
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - K Scholberg
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - A Shakirov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - G Simakov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- National Research Center "Kurchatov Institute," Moscow 123182, Russian Federation
| | - G Sinev
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - W M Snow
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - V Sosnovtsev
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - B Suh
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - R Tayloe
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | | | - I Tolstukhin
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - E Ujah
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - J Vanderwerp
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - R L Varner
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C J Virtue
- Department of Physics, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - G Visser
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - T Wongjirad
- Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155, USA
| | - Y-R Yen
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - J Yoo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - C-H Yu
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Zettlemoyer
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| |
Collapse
|
2
|
Akimov D, An P, Awe C, Barbeau PS, Becker B, Belov V, Bernardi I, Blackston MA, Bock C, Bolozdynya A, Browning J, Cabrera-Palmer B, Chernyak D, Conley E, Daughhetee J, Detwiler J, Ding K, Durand MR, Efremenko Y, Elliott SR, Fabris L, Febbraro M, Gallo Rosso A, Galindo-Uribarri A, Green MP, Heath MR, Hedges S, Hoang D, Hughes M, Johnson T, Khromov A, Konovalov A, Kozlova E, Kumpan A, Li L, Link JM, Liu J, Mann K, Markoff DM, Mastroberti J, Mueller PE, Newby J, Parno DS, Penttila SI, Pershey D, Rapp R, Ray H, Raybern J, Razuvaeva O, Reyna D, Rich GC, Ross J, Rudik D, Runge J, Salvat DJ, Salyapongse AM, Scholberg K, Shakirov A, Simakov G, Sinev G, Snow WM, Sosnovstsev V, Suh B, Tayloe R, Tellez-Giron-Flores K, Tolstukhin I, Ujah E, Vanderwerp J, Varner RL, Virtue CJ, Visser G, Wongjirad T, Yen YR, Yoo J, Yu CH, Zettlemoyer J. Measurement of the Coherent Elastic Neutrino-Nucleus Scattering Cross Section on CsI by COHERENT. Phys Rev Lett 2022; 129:081801. [PMID: 36053683 DOI: 10.1103/physrevlett.129.081801] [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: 06/02/2022] [Revised: 07/17/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in a high flux of neutrinos produced at the Spallation Neutron Source at Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled the dataset since the first observation of CEvNS, achieved with this detector. Systematic uncertainties have also been reduced with an updated quenching model, allowing for improved precision. With these analysis improvements, the COHERENT Collaboration determined the cross section to be (165_{-25}^{+30})×10^{-40} cm^{2}, consistent with the standard model, giving the most precise measurement of CEvNS yet. The timing structure of the neutrino beam has been exploited to compare the CEvNS cross section from scattering of different neutrino flavors. This result places leading constraints on neutrino nonstandard interactions while testing lepton flavor universality and measures the weak mixing angle as sin^{2}θ_{W}=0.220_{-0.026}^{+0.028} at Q^{2}≈(50 MeV)^{2}.
Collapse
Affiliation(s)
- D Akimov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - P An
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - C Awe
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - P S Barbeau
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - B Becker
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - V Belov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre "Kurchatov Institute," Moscow 117218, Russian Federation
| | - I Bernardi
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - M A Blackston
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C Bock
- Physics Department, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - A Bolozdynya
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - J Browning
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | | | - D Chernyak
- Physics Department, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - E Conley
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - J Daughhetee
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Detwiler
- Center for Experimental Nuclear Physics and Astrophysics, Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - K Ding
- Physics Department, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - M R Durand
- Center for Experimental Nuclear Physics and Astrophysics, Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Y Efremenko
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S R Elliott
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - L Fabris
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M Febbraro
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Gallo Rosso
- Department of Physics, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - A Galindo-Uribarri
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M P Green
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - M R Heath
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S Hedges
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - D Hoang
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - M Hughes
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - T Johnson
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - A Khromov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - A Konovalov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre "Kurchatov Institute," Moscow 117218, Russian Federation
| | - E Kozlova
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre "Kurchatov Institute," Moscow 117218, Russian Federation
| | - A Kumpan
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - L Li
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - J M Link
- Center for Neutrino Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - J Liu
- Physics Department, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - K Mann
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - D M Markoff
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Mathematics and Physics, North Carolina Central University, Durham, North Carolina 27707, USA
| | - J Mastroberti
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - P E Mueller
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Newby
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D S Parno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S I Penttila
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D Pershey
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - R Rapp
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - H Ray
- Department of Physics, University of Florida, Gainesville, Florida 32611, USA
| | - J Raybern
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - O Razuvaeva
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre "Kurchatov Institute," Moscow 117218, Russian Federation
| | - D Reyna
- Sandia National Laboratories, Livermore, California 94550, USA
| | - G C Rich
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - J Ross
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Mathematics and Physics, North Carolina Central University, Durham, North Carolina 27707, USA
| | - D Rudik
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - J Runge
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - D J Salvat
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - A M Salyapongse
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - K Scholberg
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - A Shakirov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - G Simakov
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre "Kurchatov Institute," Moscow 117218, Russian Federation
| | - G Sinev
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - W M Snow
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - V Sosnovstsev
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409, Russian Federation
| | - B Suh
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - R Tayloe
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | | | - I Tolstukhin
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - E Ujah
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Mathematics and Physics, North Carolina Central University, Durham, North Carolina 27707, USA
| | - J Vanderwerp
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - R L Varner
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C J Virtue
- Department of Physics, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - G Visser
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| | - T Wongjirad
- Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155, USA
| | - Y-R Yen
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - J Yoo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - C-H Yu
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Zettlemoyer
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
| |
Collapse
|