https://doi.org/10.1140/epja/s10050-025-01613-6
Regular Article - Experimental Physics
photoproduction at forward angles near threshold with the BGOOD experiment
1
Physikalisches Institut, Rheinische Friedrich-Wilhelms-Universität Bonn, Nußallee 12, 53115, Bonn, Germany
2
National Science Center “Kharkov Institute of Physics and Technology”, UA61108, Kharkov, Ukraine
3
Department of Physics, Lamar University, 77710, Beaumont, Texas, USA
4
INFN Roma “Tor Vergata”, Via della Ricerca Scientifica 1, 00133, Rome, Italy
5
Dipartimento di Fisica, Università di Roma “Tor Vergata”, Via della Ricerca Scientifica 1, 00133, Rome, Italy
6
INFN sezione di Roma La Sapienza, P.le Aldo Moro 2, 00185, Rome, Italy
7
Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
8
INFN-Laboratori Nazionali di Frascati, Via E. Fermi 54, 00044, Frascati, Italy
9
INFN sezione Catania, 95129, Catania, Italy
10
Dipartimento MIFT, Università degli Studi di Messina, Via F. S. D’Alcontres 31, 98166, Messina, Italy
11
INFN sezione di Pavia, Via Agostino Bassi, 6, 27100, Pavia, Italy
12
Institute for Nuclear Research of NASU, 03028, Kyiv, Ukraine
a
s6emrosa@uni-bonn.de
b
jude@physik.uni-bonn.de
Received:
30
October
2024
Accepted:
6
June
2025
Published online:
24
June
2025
The differential cross section for 
was measured from threshold to a centre-of-mass energy of 2090 MeV at forward angles at the BGOOD experiment. The high statistical precision and resolution in centre-of-mass energy and angle allows a detailed characterisation of this low-momentum transfer kinematic region. The data agree with a previous LEPS measurement and support effective Lagrangian models that indicate that the contact term dominates the cross section near threshold.
© The Author(s) 2025
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