https://doi.org/10.1140/epja/s10050-023-01133-1
Regular Article - Experimental Physics
Measurement of the 
differential cross section over the 
threshold
1
Rheinische Friedrich-Willhelms-Universität Bonn, Physikalisches Institut, Nußallee 12, 53115, Bonn, Germany
2
Rheinische Friedrich-Wilhelms-Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, Nußallee 14-16, 53115, Bonn, Germany
3
INFN sezione di Pavia, Via Agostino Bassi, 6, 27100, Pavia, Italy
4
Department of Physics, Lamar University, 77710, Beaumont, Texas, USA
5
INFN Roma “Tor Vergata”, Via della Ricerca Scientifica 1, 00133, Rome, Italy
6
Università di Roma “Tor Vergata”, Dipartimento di Fisica, Via della Ricerca Scientifica 1, 00133, Rome, Italy
7
INFN sezione di Roma La Sapienza, P.le Aldo Moro 2, 00185, Rome, Italy
8
Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
9
Petersburg Nuclear Physics Institute NRC “Kurchatov Institute”, 188300, Gatchina, Leningrad District, Russia
10
Russian Academy of Sciences Institute for Nuclear Research, Prospekt 60-letiya Oktyabrya 7a, 117312, Moscow, Russia
11
INFN - Laboratori Nazionali di Frascati, Via E. Fermi 54, 00044, Frascati, Italy
12
INFN sezione Catania, 95129, Catania, Italy
13
Università degli Studi di Messina, Dipartimento MIFT, Via F. S. D’Alcontres 31, 98166, Messina, Italy
14
Institute for Nuclear Research of NASU, 03028, Kyiv, Ukraine
Received:
21
December
2021
Accepted:
21
September
2023
Published online:
3
November
2023
The differential cross section for the quasi-free photoproduction reaction was measured at BGOOD at ELSA from threshold to a centre-of-mass energy of 
. Close to threshold the results are consistent with existing data and are in agreement with partial wave analysis solutions over the full measured energy range, with a large coupling to the 
evident. This is the first dataset covering the threshold region, where there are model predictions of dynamically generated vector meson-baryon resonance contributions.
V. Nedorezov and V. Sumachev are Deceased.
S. Alef, D. Hammann, B.-E. Reitz and G. Scheluchin are no longer employed in academia.
© The Author(s) 2023
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