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arXiv · 2003.11986

Demonstration of Muon-Beam Transverse Phase-Space Compression

A. Antognini·N. J. Ayres·I. Belosevic·V. Bondar·A. Eggenberger·M. Hildebrandt·R. Iwai·D. M. Kaplan·K. S. Khaw·K. Kirch·A. Knecht·A. Papa·C. Petitjean·T. J. Phillips·F. M. Piegsa·N. Ritjoho·A. Stoykov·D. Taqqu·G. Wichmann
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Abstract

We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (RMS) within 3.5 $\mu$s. The simulation including cross sections for low-energy $\mu^+$-$\text{He}$ elastic and charge exchange ($\mu^+\leftrightarrow $ muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a $\mu^+ $ beam by a factor of $ 10^{10} $ with $ 10^{-3} $ efficiency.

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A. Antognini, N. J. Ayres, I. Belosevic, V. Bondar, A. Eggenberger, M. Hildebrandt, R. Iwai, D. M. Kaplan, K. S. Khaw, K. Kirch, A. Knecht, A. Papa, C. Petitjean, T. J. Phillips, F. M. Piegsa, N. Ritjoho, A. Stoykov, D. Taqqu, G. Wichmann. 2020-03-26. Demonstration of Muon-Beam Transverse Phase-Space Compression. https://doi.org/10.1103/physrevlett.125.164802

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