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arXiv · 1803.02502

High-statistics measurement of the eta->3pi^0 decay at the Mainz Microtron

S. Prakhov·S. Abt·P. Achenbach·P. Adlarson·F. Afzal·P. Aguar-Bartolomé·Z. Ahmed·J. Ahrens·J. R. M. Annand·H. J. Arends·K. Bantawa·M. Bashkanov·R. Beck·M. Biroth·N. S. Borisov·A. Braghieri·W. J. Briscoe·S. Cherepnya·F. Cividini·C. Collicott·S. Costanza·A. Denig·M. Dieterle·E. J. Downie·P. Drexler·M. I. Ferretti Bondy·L. V. Fil'kov·A. Fix·S. Gardner·S. Garni·D. I. Glazier·I. Gorodnov·W. Gradl·G. M. Gurevich·C. B. Hamill·L. Heijkenskjöld·D. Hornidge·G. M. Huber·A. Käser·V. L. Kashevarov·S. Kay·I. Keshelashvili·R. Kondratiev·M. Korolija·B. Krusche·A. Lazarev·V. Lisin·K. Livingston·S. Lutterer·I. J. D. MacGregor·D. M. Manley·P. P. Martel·J. C. McGeorge·D. G. Middleton·R. Miskimen·E. Mornacchi·A. Mushkarenkov·A. Neganov·A. Neiser·M. Oberle·M. Ostrick·P. B. Otte·D. Paudyal·P. Pedroni·A. Polonski·G. Ron·T. Rostomyan·C. Sfienti·V. Sokhoyan·K. Spieker·O. Steffen·I. I. Strakovsky·B. Strandberg·Th. Strub·I. Supek·A. Thiel·M. Thiel·A. Thomas·M. Unverzagt·Yu. A. Usov·S. Wagner·N. K. Walford·D. P. Watts·D. Werthmüller·J. Wettig·L. Witthauer·M. Wolfes·L. A. Zana
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Abstract

The largest, at the moment, statistics of 7x10^6 eta->3pi^0 decays, based on 6.2x10^7 eta mesons produced in the gamma p -> eta p reaction, has been accumulated by the A2 Collaboration at the Mainz Microtron, MAMI. It allowed a detailed study of the eta->3pi^0 dynamics beyond its conventional parametrization with just the quadratic slope parameter alpha and enabled, for the first time, a measurement of the second-order term and a better understanding of the cusp structure in the neutral decay. The present data are also compared to recent theoretical calculations that predict a nonlinear dependence along the quadratic distance from the Dalitz-plot center.

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S. Prakhov, S. Abt, P. Achenbach, P. Adlarson, F. Afzal, P. Aguar-Bartolomé, Z. Ahmed, J. Ahrens, J. R. M. Annand, H. J. Arends, K. Bantawa, M. Bashkanov, R. Beck, M. Biroth, N. S. Borisov, A. Braghieri, W. J. Briscoe, S. Cherepnya, F. Cividini, C. Collicott, S. Costanza, A. Denig, M. Dieterle, E. J. Downie, P. Drexler, M. I. Ferretti Bondy, L. V. Fil'kov, A. Fix, S. Gardner, S. Garni, D. I. Glazier, I. Gorodnov, W. Gradl, G. M. Gurevich, C. B. Hamill, L. Heijkenskjöld, D. Hornidge, G. M. Huber, A. Käser, V. L. Kashevarov, S. Kay, I. Keshelashvili, R. Kondratiev, M. Korolija, B. Krusche, A. Lazarev, V. Lisin, K. Livingston, S. Lutterer, I. J. D. MacGregor, D. M. Manley, P. P. Martel, J. C. McGeorge, D. G. Middleton, R. Miskimen, E. Mornacchi, A. Mushkarenkov, A. Neganov, A. Neiser, M. Oberle, M. Ostrick, P. B. Otte, D. Paudyal, P. Pedroni, A. Polonski, G. Ron, T. Rostomyan, C. Sfienti, V. Sokhoyan, K. Spieker, O. Steffen, I. I. Strakovsky, B. Strandberg, Th. Strub, I. Supek, A. Thiel, M. Thiel, A. Thomas, M. Unverzagt, Yu. A. Usov, S. Wagner, N. K. Walford, D. P. Watts, D. Werthmüller, J. Wettig, L. Witthauer, M. Wolfes, L. A. Zana. 2018-03-07. High-statistics measurement of the eta->3pi^0 decay at the Mainz Microtron. https://doi.org/10.1103/physrevc.97.065203

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