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Observation of the radiative kaon decay K- --> mu-pi0gammanu

O. Tchikilev·S. Akimenko·G. Britvich·K. Datsko·A. Filin·A. Inyakin·V. Khmelnikov·S. Konstantinov·I. Korolkov·V. Leontiev·V. Novikov·V. Obraztsov·V. Polyakov·V. Romanovsky·V. Shelikhov·V. Uvarov·O. Yushchenko·V. Bolotov·S. Laptev·V. Duk·A. Polyarush
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Abstract

Using data collected with the ISTRA+ spectrometer during the 2001 run of the U-70 proton synchrotron in Protvino, we report the first observation of the radiative kaon decay K- -->mu-pi0gammanu. We find Br(Kmu3g)/Br(Kmu3) for two regions 5<Eg<30 and 30<Eg<60 MeV consistent with theoretical predictions. The measured angular distribution asymmetry for the first region, 0.093+/-0.141, is two standard deviations away from the theoretical prediction of 0.354. The measured asymmetry in the T-odd variable is -0.03+/-0.13.

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O. Tchikilev, S. Akimenko, G. Britvich, K. Datsko, A. Filin, A. Inyakin, V. Khmelnikov, S. Konstantinov, I. Korolkov, V. Leontiev, V. Novikov, V. Obraztsov, V. Polyakov, V. Romanovsky, V. Shelikhov, V. Uvarov, O. Yushchenko, V. Bolotov, S. Laptev, V. Duk, A. Polyarush. 2005-06-10. Observation of the radiative kaon decay K- --> mu-pi0gammanu. https://doi.org/10.1134/s1063778807010048

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