Evidence for Neutral-Current Diffractive π^{0} Production from Hydrogen in Neutrino Interactions on Hydrocarbon.
The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current π^{0} production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26±0.02(stat.)±0.08(sys.)×10^{-39}  cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive π^{0} production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino-oscillation experiments searching for ν_{μ} to ν_{e} oscillations.
University of Rochester, Rochester, New York 14627, USA.|Physics Department, Tufts University, Medford, Massachusetts 02155, USA.
J
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Wolcott
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Aliaga
Physics Department, Tufts University, Medford, Massachusetts 02155, USA.
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Altinok
University of Rochester, Rochester, New York 14627, USA.
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Bercellie
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Betancourt
University of Rochester, Rochester, New York 14627, USA.
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Bodek
University of Geneva, 1211 Geneva 4, Switzerland.
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Bravar
University of Rochester, Rochester, New York 14627, USA.
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Budd
University of Rochester, Rochester, New York 14627, USA.
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Cai
Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil.
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Carneiro
University of Rochester, Rochester, New York 14627, USA.
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Chvojka
Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil.
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da Motta
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Devan
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Dytman
University of Rochester, Rochester, New York 14627, USA.|Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
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Díaz
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
B
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Eberly
Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
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Endress
Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato, Guanajuato 36000, México.
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Felix
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.|Northwestern University, Evanston, Illinois 60208, USA.
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Fields
University of Rochester, Rochester, New York 14627, USA.
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Fine
Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile.
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Galindo
Physics Department, Tufts University, Medford, Massachusetts 02155, USA.
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Gallagher
University of Rochester, Rochester, New York 14627, USA.|Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Golan
Department of Physics, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA.
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Gran
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Harris
University of Rochester, Rochester, New York 14627, USA.|Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato, Guanajuato 36000, México.
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Higuera
Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil.|Universidad Nacional de Ingeniería, Apartado 31139, Lima, Perú
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Hurtado
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Kiveni
University of Rochester, Rochester, New York 14627, USA.
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J
Kleykamp
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Kordosky
Physics Department, Tufts University, Medford, Massachusetts 02155, USA.|Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
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Le
Massachusetts College of Liberal Arts, 375 Church Street, North Adams, Massachusetts 01247, USA.
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Maher
University of Rochester, Rochester, New York 14627, USA.
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Manly
Physics Department, Tufts University, Medford, Massachusetts 02155, USA.
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Mann
University of Rochester, Rochester, New York 14627, USA.
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Marshall
Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil.
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Martinez Caicedo
University of Rochester, Rochester, New York 14627, USA.|Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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McFarland
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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McGivern
University of Rochester, Rochester, New York 14627, USA.
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McGowan
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Messerly
Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile.
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Miller
University of Rochester, Rochester, New York 14627, USA.
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Mislivec
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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JG
Morfín
Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
J
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Mousseau
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Naples
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Nelson
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Norrick
Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile.|Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
Nuruzzaman
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Osta
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Paolone
University of Rochester, Rochester, New York 14627, USA.
J
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Park
Northwestern University, Evanston, Illinois 60208, USA.
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CE
Patrick
University of Rochester, Rochester, New York 14627, USA.|Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Perdue
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
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Rakotondravohitra
Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato, Guanajuato 36000, México.
M A
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Ramirez
Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
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Ray
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Ren
Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
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Rimal
University of Rochester, Rochester, New York 14627, USA.
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Rodrigues
University of Rochester, Rochester, New York 14627, USA.
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Ruterbories
Northwestern University, Evanston, Illinois 60208, USA.|Department of Physics, Oregon State University, Corvallis, Oregon 97331, USA.
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Schellman
Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.|Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA.
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Schmitz
Universidad Nacional de Ingeniería, Apartado 31139, Lima, Perú
C J
CJ
Solano Salinas
Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
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Sánchez Falero
Department of Physics, Otterbein University, 1 South Grove Street, Westerville, Ohio 43081, USA.
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Tagg
Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
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Tice
Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato, Guanajuato 36000, México.
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Valencia
Department of Physics, Hampton University, Hampton, Virginia 23668, USA.
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Walton
Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
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Wospakrik
Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA.
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Zhang