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arXiv · hep-ex/9912062

Search for a 33.9 MeV/c^2 Neutral Particle in Pion Decay

J. A. Formaggio·E. D. Zimmerman·T. Adams·A. Alton·S. Avvakumov·L. de Barbaro·P. de Barbaro·R. H. Bernstein·A. Bodek·T. Bolton·J. Brau·D. Buchholz·H. Budd·L. Bugel·S. Case·J. M. Conrad·R. B. Drucker·B. T. Fleming·R. Frey·J. Goldman·M. Goncharov·D. A. Harris·R. A. Johnson·J. H. Kim·S. Koutsoliotas·M. J. Lamm·W. Marsh·D. Mason·K. S. McFarland·C. McNulty·D. Naples·P. Nienaber·A. Romosan·W. K. Sakumoto·H. M. Schellman·M. H. Shaevitz·P. Spentzouris·E. G. Stern·M. Vakili·A. Vaitaitis·V. Wu·U. K. Yang·J. Yu·G . P. Zeller
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Abstract

The E815 (NuTeV) neutrino experiment has performed a search for a 33.9 MeV/c^2 weakly-interacting neutral particle produced in pion decay. Such a particle may be responsible for an anomaly in the timing distribution of neutrino interactions in the KARMEN experiment. E815 has searched for this particle's decays in an instrumented decay region; no evidence for this particle was found. The search is sensitive to pion branching ratios as low as 10^-13.

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J. A. Formaggio, E. D. Zimmerman, T. Adams, A. Alton, S. Avvakumov, L. de Barbaro, P. de Barbaro, R. H. Bernstein, A. Bodek, T. Bolton, J. Brau, D. Buchholz, H. Budd, L. Bugel, S. Case, J. M. Conrad, R. B. Drucker, B. T. Fleming, R. Frey, J. Goldman, M. Goncharov, D. A. Harris, R. A. Johnson, J. H. Kim, S. Koutsoliotas, M. J. Lamm, W. Marsh, D. Mason, K. S. McFarland, C. McNulty, D. Naples, P. Nienaber, A. Romosan, W. K. Sakumoto, H. M. Schellman, M. H. Shaevitz, P. Spentzouris, E. G. Stern, M. Vakili, A. Vaitaitis, V. Wu, U. K. Yang, J. Yu, G . P. Zeller. 1999-12-24. Search for a 33.9 MeV/c^2 Neutral Particle in Pion Decay. https://doi.org/10.1103/physrevlett.84.4043

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