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arXiv · hep-ex/9711023

Evidence of phi --> pi0 pi0 gamma and phi --> pi0 eta gamma decays in SND experiment at VEPP-2M

M. N. Achasov·A. V. Berdyugin·A. V. Bozhenok·A. D. Bukin·D. A. Bukin·S. V. Burdin·T. V. Dimova·V. P. Druzhinin·M. S. Dubrovin·I. A. Gaponenko·V. B. Golubev·V. N. Ivanchenko·I. A. Koop·A. A. Korol·S. V. Koshuba·E. V. Pakhtusova·A. A. Salnikov·S. I. Serednyakov·V. V. Shary·Yu. M. Shatunov·V. A. Sidorov·Z. K. Silagadze·A. N. Skrinsky·Yu. V. Usov
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Abstract

Preliminary results on the study of e+e- --> phi(1020) --> pi0 pi0 gamma, eta pi0 gamma processes from SND experiment at VEPP-2M collider in Novosibirsk are presented. Branching ratios of rare radiative phi --> pi0 pi0 gamma and phi --> pi0 eta gamma decays are measured: B(phi --> pi0 pi0 gamma ) = (1.1 +- 0.2) * 10^-4 (invariant mass (pi0 pi0) < 800 MeV), B(phi --> eta pi0 gamma ) = (1.3 +- 0.5) * 10^-4.

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M. N. Achasov, A. V. Berdyugin, A. V. Bozhenok, A. D. Bukin, D. A. Bukin, S. V. Burdin, T. V. Dimova, V. P. Druzhinin, M. S. Dubrovin, I. A. Gaponenko, V. B. Golubev, V. N. Ivanchenko, I. A. Koop, A. A. Korol, S. V. Koshuba, E. V. Pakhtusova, A. A. Salnikov, S. I. Serednyakov, V. V. Shary, Yu. M. Shatunov, V. A. Sidorov, Z. K. Silagadze, A. N. Skrinsky, Yu. V. Usov. 1997-11-27. Evidence of phi --> pi0 pi0 gamma and phi --> pi0 eta gamma decays in SND experiment at VEPP-2M. https://doi.org/10.1063/1.56103

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