New Bounds from Searching for Muonium to Antimuonium Conversion

L. Willmann; P. V. Schmidt; H. P. Wirtz; R. Abela; V. Baranov; J. Bagaturia; W. Bertl; R. Engfer; A. Grossmann; V. W. Hughes; K. Jungmann; V. Karpuchin; I. Kisel; A. Korenchenko; S. Korenchenko; N. Kravchuk; N. Kuchinsky; A. Leuschner; V. Meyer; J. Merkel; A. Moiseenko; D. Mzavia; G. zu Putlitz; W. Reichart; I. Reinhard; D. Renker; T. Sakhelashvilli; K. Tr"ager; H. K. Walter

doi:10.1103/physrevlett.82.49

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arXiv · hep-ex/9807011

New Bounds from Searching for Muonium to Antimuonium Conversion

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Abstract

A new upper limit for the probability of spontaneous muonium to antimuonium conversion was established at ${\rm P_{M\bar{M}}} \leq 8.2 \cdot 10^{-11}$ (90%C.L.) in 0.1~T magnetic field, which implies consequences for speculative extensions to the standard model. Coupling parameters in R-parity violating supersymmetry and the mass of a flavour diagonal bileptonic gauge boson can be significantly restricted. A Z$_8$ model with radiative mass generation through heavy lepton seed and the minimal version of 331-GUT models are ruled out.

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L. Willmann, P. V. Schmidt, H. P. Wirtz, R. Abela, V. Baranov, J. Bagaturia, W. Bertl, R. Engfer, A. Grossmann, V. W. Hughes, K. Jungmann, V. Karpuchin, I. Kisel, A. Korenchenko, S. Korenchenko, N. Kravchuk, N. Kuchinsky, A. Leuschner, V. Meyer, J. Merkel, A. Moiseenko, D. Mzavia, G. zu Putlitz, W. Reichart, I. Reinhard, D. Renker, T. Sakhelashvilli, K. Tr"ager, H. K. Walter. 1998-07-10. New Bounds from Searching for Muonium to Antimuonium Conversion. https://doi.org/10.1103/physrevlett.82.49

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