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arXiv · 0804.4841

Quasi-free photoproduction of eta-mesons of the neutron

I. Jaegle·T. Mertens·A. V. Anisovich·J. C. S. Bacelar·B. Bantes·O. Bartholomy·D. Bayadilov·R. Beck·Y. A. Beloglazov·R. Castelijns·V. Crede·H. Dutz·A. Ehmanns·D. Elsner·K. Essig·R. Ewald·I. Fabry·M. Fuchs·C. Funke·R. Gothe·R. Gregor·A. B. Gridnev·E. Gutz·S. Hoeffgen·P. Hoffmeister·I. Horn·J. Junkersfeld·H. Kalinowsky·S. Kammer·V. Kleber·Frank Klein·Friedrich Klein·E. Klempt·M. Konrad·M. Kotulla·B. Krusche·M. Lang·J. Langheinrich·H. Loehner·I. V. Lopatin·J. Lotz·S. Lugert·D. Menze·J. G. Messchendorp·V. Metag·C. Morales·M. Nanova·V. A. Nikonov·D. V. Novinski·R. Novotny·M. Ostrick·L. M. Pant·H. van Pee·M. Pfeiffer·A. K. Radkov·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·C. Weinheimer·C. Wendel
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Abstract

Quasi-free photoproduction of eta-mesons off nucleons bound in the deuteron has been measured with the CBELSA/TAPS detector for incident photon energies up to 2.5 GeV at the Bonn ELSA accelerator. The eta-mesons have been detected in coincidence with recoil protons and recoil neutrons, which allows a detailed comparison of the quasi-free n(gamma,eta)n and p(gamma,eta)p reactions. The excitation function for eta-production off the neutron shows a pronounced bump-like structure at W=1.68 GeV (E_g ~ 1 GeV), which is absent for the proton.

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I. Jaegle, T. Mertens, A. V. Anisovich, J. C. S. Bacelar, B. Bantes, O. Bartholomy, D. Bayadilov, R. Beck, Y. A. Beloglazov, R. Castelijns, V. Crede, H. Dutz, A. Ehmanns, D. Elsner, K. Essig, R. Ewald, I. Fabry, M. Fuchs, C. Funke, R. Gothe, R. Gregor, A. B. Gridnev, E. Gutz, S. Hoeffgen, P. Hoffmeister, I. Horn, J. Junkersfeld, H. Kalinowsky, S. Kammer, V. Kleber, Frank Klein, Friedrich Klein, E. Klempt, M. Konrad, M. Kotulla, B. Krusche, M. Lang, J. Langheinrich, H. Loehner, I. V. Lopatin, J. Lotz, S. Lugert, D. Menze, J. G. Messchendorp, V. Metag, C. Morales, M. Nanova, V. A. Nikonov, D. V. Novinski, R. Novotny, M. Ostrick, L. M. Pant, H. van Pee, M. Pfeiffer, A. K. Radkov, 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, C. Weinheimer, C. Wendel. 2008-04-30. Quasi-free photoproduction of eta-mesons of the neutron. https://doi.org/10.1103/physrevlett.100.252002

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