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arXiv · 0812.2829

Precise Measurement of pi+ -> e+ nu Branching Ratio

E. Frlež·L. P. Alonzi·V. A. Baranov·W. Bertl·M. Bychkov·Yu. M. Bystritsky·N. V. Khomutov·A. S. Korenchenko·S. M. Korenchenko·M. Korolija·T. Kozlowski·N. P. Kravchuk·N. A. Kuchinsky·D. Mekterović·D. Mzhavia·A. Palladino·D. Počanić·P. Robmann·A. M. Rozhdestvensky·V. V. Sidorkin·U. Straumann·I. Supek·P. Truöl·A. van der Schaaf·E. P. Velicheva·V. P. Volnykh
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Abstract

The PEN Collaboration is conducting a new measurement of the pi+ -> e+ nu branching ratio at the Paul Scherrer Institute, with the goal uncertainty of delta B/B(pie2)=5E-4 or lower. At present, the combined accuracy of all published pie2 decay measurements lags behind the theoretical calculation by a factor of 40. In this contribution we report on the PEN detector configuration and its performance during two development runs done in 2007 and 2008.

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E. Frlež, L. P. Alonzi, V. A. Baranov, W. Bertl, M. Bychkov, Yu. M. Bystritsky, N. V. Khomutov, A. S. Korenchenko, S. M. Korenchenko, M. Korolija, T. Kozlowski, N. P. Kravchuk, N. A. Kuchinsky, D. Mekterović, D. Mzhavia, A. Palladino, D. Počanić, P. Robmann, A. M. Rozhdestvensky, V. V. Sidorkin, U. Straumann, I. Supek, P. Truöl, A. van der Schaaf, E. P. Velicheva, V. P. Volnykh. 2008-12-15. Precise Measurement of pi+ -> e+ nu Branching Ratio. https://doi.org/10.1007/978-90-481-2287-5_10

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