@article{8cfd9aa31a704a8682bc6ec4ab78b0fb,
title = "Detector for measuring the π+ → e+νe branching fraction",
abstract = "The PIENU experiment at TRIUMF is aimed at a measurement of the branching ratio Re/μ = Γ((π+→e+νe)+(π+→e+νeγ))/Γ((π+→μ+νμ)+(π+→μ+νμγ)) with precision <0.1%. Incident pions, delivered at the rate of 60 kHz with momentum 75 MeV/c, were degraded and stopped in a plastic scintillator target. Pions and their decay product positrons were detected with plastic scintillators and tracked with multiwire proportional chambers and silicon strip detectors. The energies of the positrons were measured in a spectrometer consisting of a large NaI(Tl) crystal surrounded by an array of pure CsI crystals. This paper provides a description of the PIENU experimental apparatus and its performance in pursuit of Re/μ.",
keywords = "CsI, NaI(Tl), Pion decay, Scintillation detectors",
author = "Aguilar-Arevalo, {A. A.} and M. Aoki and M. Blecher and {Vom Bruch}, D. and D. Bryman and J. Comfort and S. Cuen-Rochin and L. Doria and P. Gumplinger and A. Hussein and Y. Igarashi and N. Ito and S. Ito and Kettell, {S. H.} and L. Kurchaninov and L. Littenberg and C. Malbrunot and Mischke, {R. E.} and A. Muroi and T. Numao and G. Sheffer and A. Sher and T. Sullivan and K. Tauchi and D. Vavilov and K. Yamada and M. Yoshida",
note = "Funding Information: We wish to thank P. Amaudruz, R. Bula, S. Chan, M. Constable, C. Lim, N. Khan, R. Kokke, P. Lu, K. Olchanski, R. Openshaw, C. Pearson and R. Poutissou for their contributions to the engineering, installation and commissioning of the detector and DAQ-related work. We are also grateful to Brookhaven National Laboratory for providing the NaI(Tℓ) and CsI crystals. This work was supported by the Natural Science and Engineering Council (NSERC) and the National Research Council of Canada through its contribution to TRIUMF and supported by JSPS KAKENHI Grant numbers 18540274 , 21340059 , 24224006 . Publisher Copyright: {\textcopyright} 2015 Elsevier B.V.",
year = "2015",
month = apr,
day = "25",
doi = "10.1016/j.nima.2015.04.004",
language = "English (US)",
volume = "791",
pages = "38--46",
journal = "Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment",
issn = "0168-9002",
publisher = "Elsevier",
}