https://doi.org/10.1051/epjconf/201919902009
Resonances in forward π+π− photoproduction on hydrogen
1 Institute of Computer Science, Pedagogical University of Cracow, Kraków, Poland
2 Nuclear Physics Institute, ASCR, Řež/Prague, Czech Republic
3 Institute of Nuclear Physics PAS, Kraków, Poland
4 Physics Department, Indiana University, Bloomington, IN 47405, USA
5 Center for Exploration of Energy and Matter, Indiana University, Bloomington, IN 47403, USA
6 Theory Center, Thomas Jefferson National Accelerator Facility
* e-mail: lukasz.bibrzycki@up.krakow.pl
Published online: 1 February 2019
We show that the cross section of the Δ(1230) production in the γp → pπ+ π− reaction at forward angles and with unpolarized photons can be described in terms of gauge invariant one pion t-channel exchange amplitudes. Proper description of the polarized cross sections requires, however, the inclusion of contributions from the baryon exchanges.
© The Authors, published by EDP Sciences, 2019
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