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arXiv · 1107.2151

Photoproduction of Neutral Pions off Protons

Abstract

Photoproduction of neutral pions has been studied with the CBELSA/TAPS detector in the reaction $\gamma p\to p\pi^0$ for photon energies between 0.85 and 2.50 GeV. The $\pi^0$ mesons are observed in their dominant neutral decay mode: $\pi^0\to\gamma\gamma$. For the first time, the differential cross sections cover the very forward region, $\theta_{\rm c.m.}<60^\circ$. A partial-wave analysis of these data within the Bonn-Gatchina framework observes the high-mass resonances $G_{17}$(2190), $D_{13}$(2080), and $D_{15}$(2070).

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TAPS Collaboration, V. Crede, N. Sparks, A. Wilson, A. V. Anisovich, J. C. S. Bacelar, R. Bantes, O. Bartholomy, D. Bayadilov, R. Beck, Y. A. Beloglazov, R. Castelijns, H. Dutz, D. Elsner, R. Ewald, F. Frommberger, Chr. Funke, R. Gregor, A. Gridnev, E. Gutz, W. Hillert, P. Hoffmeister, I. Jaegle, J. Junkersfeld, H. Kalinowsky, S. Kammer, Frank Klein, Friedrich Klein, E. Klempt, M. Kotulla, B. Krusche, H. Loehner, I. V. Lopatin, S. Lugert, D. Menze, T. Mertens, J. G. Messchendorp, V. Metag, M. Nanova, V. A. Nikonov, D. Novinski, R. Novotny, M. Ostrick, L. M. Pant, H. van Pee, M. Pfeiffer, A. Roy, A. V. Sarantsev, S. Schadmand, C. Schmidt, H. Schmieden, B. Schoch, S. Shende, V. Sokhoyan, A. Suele, V. V. Sumachev, T. Szczepanek, U. Thoma, D. Trnka, R. Varma, D. Walther, Ch. Wendel. 2011-07-11. Photoproduction of Neutral Pions off Protons. https://doi.org/10.1103/physrevc.84.055203

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