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Measurement of the rate of formation of pi-mu atoms in KL0 decay

S. H. Aronson, R. H. Bernstein, G. J. Bock, R. D. Cousins, Jr., J. F. Greenhalgh, D. Hedin, M. Schwartz, T. K. Shea, G. B. Thomson et al.

B. Winstein

  • Brookhaven National Laboratory, Upton, New York 11973
  • University of Chicago, Chicago, Illinois 60637
  • Stanford University, Stanford, California 94305
  • University of Wisconsin, Madison, Wisconsin 53706

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Phys. Rev. D 33, 3180 – Published 1 June, 1986

DOI: https://doi.org/10.1103/PhysRevD.33.3180

Abstract

Hydrogenlike atoms consisting of a pion and a muon can be formed in KL0→πμν decays. In an experiment at Fermilab, 320 pi-mu atoms were detected and simultaneously the KL0 flux was monitored by recording ordinary KL0→πμν decays. The first measurement of the branching ratio R=Γ(KL0→pi-mu atom+ν)/Γ(KL0→πμν)=(3.90 ±0.39)×10−7 is reported, based on a subset of 155 atoms. This ratio may be sensitive to anomalous interactions between the pion and the muon. In the absence of such interactions, theory predicts R=(4.31±0.08)×10−7..AE

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References (29)

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Phys. Rev. D 33, 3180– Published 1 June, 1986
  • Received 13 January 1986

© 1986 American Physical Society

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