Abstract
Experiments with muons (μ+) and muonium atoms (μ+e−) offer several promising possibilities for testing fundamental symmetries. Examples of such experiments include the search for a muon electric dipole moment, measurement of the muon g − 2 and experiments with muonium from laser spectroscopy to gravity experiments. These experiments require high quality muon beams with small transverse size and high intensity at low energy. At the Paul Scherrer Institute, Switzerland, we are developing a novel device that reduces the phase space of a standard μ+ beam by a factor of 1010 with 10− 3 efficiency. The phase space compression is achieved by stopping a standard μ+ beam in cryogenic helium gas. The stopped μ+ are manipulated into a small spot using complex electric and magnetic fields in combination with gas density gradients. From there, the muons are extracted into the vacuum and into a field-free region. Various aspects of this compression scheme have been demonstrated. In this article the current status will be reported.
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Acknowledgements
This work was supported by the SNF grants No. 200020_159754 and 200020_172639.
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This article is part of the Topical Collection on Proceedings of the 7th International Conference on Trapped Charged Particles and Fundamental Physics (TCP 2018), Traverse City, Michigan, USA, 30 September-5 October 2018
Edited by Ryan Ringle, Stefan Schwarz, Alain Lapierre, Oscar Naviliat-Cuncic, Jaideep Singh and Georg Bollen
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Belosevic, I., Antognini, A., Bao, Y. et al. muCool: a novel low-energy muon beam for future precision experiments. Hyperfine Interact 240, 41 (2019). https://doi.org/10.1007/s10751-019-1589-4
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DOI: https://doi.org/10.1007/s10751-019-1589-4