A Measurement of Proton, Deuteron, Triton and Alpha Particle Emission after Nuclear Muon Capture on Al, Si and Ti with the AlCap Experiment

AlCap Collaboration; Andrew Edmonds; John Quirk; Ming-Liang Wong; Damien Alexander; Robert H. Bernstein; Aji Daniel; Eleonora Diociaiuti; Raffaella Donghia; Ewen L. Gillies; Ed V. Hungerford; Peter Kammel; Benjamin E. Krikler; Yoshitaka Kuno; Mark Lancaster; R. Phillip Litchfield; James P. Miller; Anthony Palladino; Jose Repond; Akira Sato; Ivano Sarra; Stefano Roberto Soleti; Vladimir Tishchenko; Nam H. Tran; Yoshi Uchida; Peter Winter; Chen Wu

arXiv · 2110.10228

A Measurement of Proton, Deuteron, Triton and Alpha Particle Emission after Nuclear Muon Capture on Al, Si and Ti with the AlCap Experiment

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Abstract

Heavy charged particles after nuclear muon capture are an important nuclear physics background to the muon-to-electron conversion experiments Mu2e and COMET, which will search for charged lepton flavor violation at an unprecedented level of sensitivity. The AlCap experiment measured the yield and energy spectra of protons, deuterons, tritons, and alpha particles emitted after the nuclear capture of muons stopped in Al, Si, and Ti in the low energy range relevant for the muon-to-electron conversion experiments. Individual charged particle types were identified in layered silicon detector packages and their initial energy distributions were unfolded from the observed energy spectra. Detailed information on yields and energy spectra for all observed nuclei are presented in the paper.

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AlCap Collaboration, Andrew Edmonds, John Quirk, Ming-Liang Wong, Damien Alexander, Robert H. Bernstein, Aji Daniel, Eleonora Diociaiuti, Raffaella Donghia, Ewen L. Gillies, Ed V. Hungerford, Peter Kammel, Benjamin E. Krikler, Yoshitaka Kuno, Mark Lancaster, R. Phillip Litchfield, James P. Miller, Anthony Palladino, Jose Repond, Akira Sato, Ivano Sarra, Stefano Roberto Soleti, Vladimir Tishchenko, Nam H. Tran, Yoshi Uchida, Peter Winter, Chen Wu. 2021-10-19. A Measurement of Proton, Deuteron, Triton and Alpha Particle Emission after Nuclear Muon Capture on Al, Si and Ti with the AlCap Experiment. https://arxiv.org/abs/2110.10228

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