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arXiv · hep-ex/0609007

Measurement of the eta->pi+pi-e+e- decay branching ratio

WASA Collaboration·Chr. Bargholtz·M. Bashkanov·D. Bogoslawsky·H. Calén·F. Capellaro·H. Clement·L. Demirörs·C. Ekström·K. Fransson·L. Gerén·L. Gustafsson·B. Höistad·G. Ivanov·M. Jacewicz·E. Jiganov·T. Johansson·S. Keleta·I. Koch·S. Kullander·A. Kupsc·A. Kuznetsov·I. V. Laukhin·K. Lindberg·P. Marciniewski·R. Meier·B. Morosov·W. Oelert·C. Pauly·H. Pettersson·Y. Petukhov·A. Povtorejko·R. J. M. Y. Ruber·K. Schönning·W. Scobel·R. Shafigullin·B. Shwartz·T. Skorodko·V. Sopov·J. Stepaniak·V. Tchernyshev·P. -E. Tegnér·P. Thörngren Engblom·V. Tikhomirov·A. Turowiecki·G. J. Wagner·M. Wolke·A. Yamamoto·J. Zabierowski·I. Zartova·J. Złomańczuk
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Abstract

The reaction pd->3He eta at threshold was used to provide a clean source of eta mesons for decay studies with the WASA detector at CELSIUS. The branching ratio of the decay eta->pi+pi-e+e- is measured to be (4.3+/-1.3+/-0.4)x10^-4.

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WASA Collaboration, Chr. Bargholtz, M. Bashkanov, D. Bogoslawsky, H. Calén, F. Capellaro, H. Clement, L. Demirörs, C. Ekström, K. Fransson, L. Gerén, L. Gustafsson, B. Höistad, G. Ivanov, M. Jacewicz, E. Jiganov, T. Johansson, S. Keleta, I. Koch, S. Kullander, A. Kupsc, A. Kuznetsov, I. V. Laukhin, K. Lindberg, P. Marciniewski, R. Meier, B. Morosov, W. Oelert, C. Pauly, H. Pettersson, Y. Petukhov, A. Povtorejko, R. J. M. Y. Ruber, K. Schönning, W. Scobel, R. Shafigullin, B. Shwartz, T. Skorodko, V. Sopov, J. Stepaniak, V. Tchernyshev, P. -E. Tegnér, P. Thörngren Engblom, V. Tikhomirov, A. Turowiecki, G. J. Wagner, M. Wolke, A. Yamamoto, J. Zabierowski, I. Zartova, J. Złomańczuk. 2006-11-21. Measurement of the eta->pi+pi-e+e- decay branching ratio. https://doi.org/10.1016/j.physletb.2006.12.008

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