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arXiv · 1506.08849

Measurement of pi^0 photoproduction on the proton at MAMI C

P. Adlarson·F. Afzal·C. S. Akondi·J. R. M. Annand·H. J. Arends·Ya. I. Azimov·R. Beck·N. Borisov·A. Braghieri·W. J. Briscoe·S. Cherepnya·F. Cividini·C. Collicott·S. Costanza·A. Denig·E. J. Downie·M. Dieterle·M. I. Ferretti Bondy·L. V. Fil'kov·A. Fix·S. Gardner·S. Garni·D. I. Glazier·D. Glowa·W. Gradl·G. Gurevich·D. J. Hamilton·D. Hornidge·G. M. Huber·A. Käser·V. L. Kashevarov·S. Kay·I. Keshelashvili·R. Kondratiev·M. Korolija·B. Krusche·V. V. Kulikov·A. Lazarev·J. Linturi·V. Lisin·K. Livingston·I. J. D. MacGregor·D. M. Manley·P. P. Martel·M. Martemianov·J. C. McGeorge·W. Meyer·D. G. Middleton·R. Miskimen·A. Mushkarenkov·A. Neganov·A. Neiser·M. Oberle·M. Ostrick·P. Ott·P. B. Otte·B. Oussena·D. Paudyal·P. Pedroni·A. Polonski·V. V. Polyanski·S. Prakhov·A. Rajabi·G. Reicherz·G. Ron·T. Rostomyan·A. Sarty·D. M. Schott·S. Schumann·C. Sfienti·V. Sokhoyan·K. Spieker·O. Steffen·I. I. Strakovsky·Th. Strub·I. Supek·M. F. Taragin·A. Thiel·M. Thiel·L. Tiator·A. Thomas·M. Unverzagt·Yu. A. Usov·S. Wagner·D. P. Watts·D. Werthmüller·J. Wettig·L. Witthauer·M. Wolfes·R. L. Workman·L. A. Zana
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Abstract

Differential cross sections for the gamma p -> pi^0 p reaction have been measured with the A2 tagged-photon facilities at the Mainz Microtron, MAMI C, up to the center-of-mass energy W=1.9 GeV. The new results, obtained with a fine energy and angular binning, increase the existing quantity of pi^0 photoproduction data by ~47%. Owing to the unprecedented statistical accuracy and the full angular coverage, the results are sensitive to high partial-wave amplitudes. This is demonstrated by the decomposition of the differential cross sections in terms of Legendre polynomials and by further comparison to model predictions. A new solution of the SAID partial-wave analysis obtained after adding the new data into the fit is presented.

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P. Adlarson, F. Afzal, C. S. Akondi, J. R. M. Annand, H. J. Arends, Ya. I. Azimov, R. Beck, N. Borisov, A. Braghieri, W. J. Briscoe, S. Cherepnya, F. Cividini, C. Collicott, S. Costanza, A. Denig, E. J. Downie, M. Dieterle, M. I. Ferretti Bondy, L. V. Fil'kov, A. Fix, S. Gardner, S. Garni, D. I. Glazier, D. Glowa, W. Gradl, G. Gurevich, D. J. Hamilton, D. Hornidge, G. M. Huber, A. Käser, V. L. Kashevarov, S. Kay, I. Keshelashvili, R. Kondratiev, M. Korolija, B. Krusche, V. V. Kulikov, A. Lazarev, J. Linturi, V. Lisin, K. Livingston, I. J. D. MacGregor, D. M. Manley, P. P. Martel, M. Martemianov, J. C. McGeorge, W. Meyer, D. G. Middleton, R. Miskimen, A. Mushkarenkov, A. Neganov, A. Neiser, M. Oberle, M. Ostrick, P. Ott, P. B. Otte, B. Oussena, D. Paudyal, P. Pedroni, A. Polonski, V. V. Polyanski, S. Prakhov, A. Rajabi, G. Reicherz, G. Ron, T. Rostomyan, A. Sarty, D. M. Schott, S. Schumann, C. Sfienti, V. Sokhoyan, K. Spieker, O. Steffen, I. I. Strakovsky, Th. Strub, I. Supek, M. F. Taragin, A. Thiel, M. Thiel, L. Tiator, A. Thomas, M. Unverzagt, Yu. A. Usov, S. Wagner, D. P. Watts, D. Werthmüller, J. Wettig, L. Witthauer, M. Wolfes, R. L. Workman, L. A. Zana. 2015-06-29. Measurement of pi^0 photoproduction on the proton at MAMI C. https://doi.org/10.1103/physrevc.92.024617

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