%0 Electronic Article
%A WASA-at-COSY Collaboration
%A Adlarson, P.
%A Augustyniak, W.
%A Bardan, W.
%A Bashkanov, M.
%A Bergmann, F. S.
%A Berłowski, M.
%A Bondar, A.
%A Calen, H.
%A Ciepał, I.
%A Clement, H.
%A Czerwinski, E.
%A Demmich, K.
%A Engels, Ralf W.
%A Erven, A.
%A Erven, W.
%A Eyrich, W.
%A Fedorets, P.
%A Föhl, K.
%A Fransson, K.
%A Goldenbaum, F.
%A Grigoryev, A. Goswami K.
%A Gullström, C. -O.
%A Heijkenskjöld, L.
%A Hejny, V.
%A Hüsken, N.
%A Jarczyk, L.
%A Johansson, T.
%A Kamys, B.
%A Kemmerling, G.
%A Khatri, G.
%A Khoukaz, A.
%A Khreptak, O.
%A Kirillov, D. A.
%A Kistryn, S.
%A Kleines, Harald
%A Kłos, B.
%A Krzemien, W.
%A Kulessa, P.
%A Kuzmin, A.
%A Lalwani, K.
%A Lersch, D.
%A Lorentz, B.
%A Magiera, A.
%A Maier, R.
%A Marciniewski, P.
%A Marianski, B.
%A Morsch, H. -P.
%A Ohm, H.
%A Parol, W.
%A del Rio, E. Perez
%A Piskunov, N. M.
%A Prasuhn, D.
%A Pszczel, D.
%A Pysz, K.
%A Pyszniak, A.
%A Ritman, J.
%A Roy, A.
%A Rudy, Z.
%A Rundel, O.
%A Sawant, S.
%A Schadmand, S.
%A Schätti-Ozerianska, I.
%A Sefzick, T.
%A Serdyuk, V.
%A Shwartz, B.
%A Sitterberg, K.
%A Skorodko, T.
%A Skurzok, M.
%A Smyrski, J.
%A Sopov, V.
%A Stassen, R.
%A Stepaniak, J.
%A Stephan, E.
%A Sterzenbach, G.
%A Stockhorst, H.
%A Ströher, H.
%A Szczurek, A.
%A Trzcinski, A.
%A Varma, R.
%A Wronska, A.
%A Wüstner, P.
%A Yamamoto, A.
%A Zabierowski, J.
%A Zielinski, M. J.
%A Złomanczuk, J.
%A Zupranski, P.
%A Zurek, M.
%A Büscher, Markus
%A Moskal, P.
%A Wolke, M.
%A Kupsc, A.
%T Isoscalar Single-Pion Production in the Region of Roper and $d^*(2380)$ Resonances
%M FZJ-2017-05279
%D 2017
%X Exclusive measurements of the quasi-free $pn \to pp\pi^-$ and $pp \to pp\pi^0$ reactions have been performed by means of $pd$ collisions at $T_p$ = 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $T_p = 0.95 - 1.3$ GeV ($\sqrt s$ = 2.3 - 2.46 GeV), which includes the regions of $\Delta(1232)$, $N^*(1440)$ and $d^*(2380)$ resonance excitations. From these measurements the isoscalar single-pion production has been extracted, for which data existed so far only below $T_p$ = 1 GeV. We observe a substantial increase of this cross section above 1 GeV, which can be related to the Roper resonance $N^*(1440)$, the strength of which shows up isolated from the $\Delta$ resonance in the isoscalar $(N\pi)_{I=0}$ invariant-mass spectrum. No evidence for a decay of the dibaryon resonance $d^*(2380)$ into the isoscalar $(NN\pi)_{I=0}$ channel is found. An upper limit of 180 $\mu$b (90 $\%$ C.L.) corresponding to a branching ratio of 9 $\%$ has been deduced.
%F PUB:(DE-HGF)25
%9 Preprint
%U https://juser.fz-juelich.de/record/836156