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Search for Free Decay of Negative Pions in Water and Light Materials

T. Numao·Yu. I. Davydov·J-M. Poutissou·T. C. Awes·V. Cianciolo·S. Berridge·W. Bugg·Yu. Efremenko·R. Gearhart·S. Ovchinnikov
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Abstract

We report on a search for the free decay component of pi- stopped in water and light materials. A non-zero value of this would be an indication of anomalous nu_e contamination to the nu_e and nu_mu_bar production at stopped-pion neutrino facilities. No free decay component of pi- was observed in water, Beryllium, and Aluminum, for which upper limits were established at 8.2E-4, 3.2E-3, and 7.7E-3, respectively.

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T. Numao, Yu. I. Davydov, J-M. Poutissou, T. C. Awes, V. Cianciolo, S. Berridge, W. Bugg, Yu. Efremenko, R. Gearhart, S. Ovchinnikov. 2006-05-30. Search for Free Decay of Negative Pions in Water and Light Materials. https://doi.org/10.1103/physrevd.73.092004

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