Measurement of the η→3π0 Dalitz plot distribution with the WASA detector at COSY

• Published in: Physics letters. B 2009-06, Vol.677 (1-2), p.24-29
• Main Authors: Adolph, C., Angelstein, M., Bashkanov, M., Bechstedt, U., Belostotski, S., Berłowski, M., Bhatt, H., Bisplinghoff, J., Bondar, A., Borasoy, B., Clement, H., Czerwiński, E., Czyżykiewicz, R., D'Orsaneo, G., Duniec, D., Ekström, C., Engels, R., Erven, W., Eyrich, W., Felden, O., Fransson, K., Gil, D., Goldenbaum, F., Grigoryev, K., Heczko, A., Hejny, V., Hinterberger, F., Izotov, A., Janusz, M., Kamys, B., Kemmerling, G., Keshelashvili, I., Khakimova, O., Khoukaz, A., Kilian, K., Kistryn, S., Klaja, J., Klaja, P., Kleines, H., Klos, B., Kowalczyk, A., Kulessa, P., Kupść, A., Kuzmin, A., Kyryanchuk, V., Maier, R., Marciniewski, P., Migdał, W., Meißner, U.-G., Mikirtychiants, M., Miklukho, O., Milke, N., Mittag, M., Moskal, P., Nandi, B.K., Odoyo, M.A., Oelert, W., Ohm, H., Paul, N., Pauly, C., Petukhov, Y., Pluciński, P., Podkopał, P., Prasuhn, D., Rachowski, J., Redmer, C.F., Ritman, J., Roy, A., Ruber, R.J.M.Y., Rudy, Z., Salmin, R., Schadmand, S., Scobel, W., Sefzick, T., Serdyuk, V., Shah, N., Skorodko, T., Smoliński, T., Smyrski, J., Spölgen, D., Sterzenbach, G., Ströher, H., Tolba, T., Trzciński, A., Ulbrich, K., Varma, R., Vlasov, P., Winnemöller, A., Wirzba, A., Wrońska, A., Wüstner, P., Xu, H., Yuan, X., Yurev, L., Zabierowski, J., Zheng, C., Zieliński, M.J., Zipper, W., Zwoll, K., Zychor, I.
• Format: Article
• Language: English
• Subjects: Dalitz plot; Exact sciences and technology; formula omitted; Nuclear physics; Physics; The physics of elementary particles and fields
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2009.03.063

In the first production run of the WASA experiment at COSY, the eta decay into three neutral pions was measured in proton–proton interactions at a proton beam kinetic energy of 1.4 GeV. The Dalitz plot of the three pions was studied using 1.2×105 fully reconstructed events, and the quadratic slope parameter α was determined to be −0.027±0.008(stat)±0.005(syst). The result is consistent with previous measurements and further corroborates the importance of pion–pion final state interactions.