https://doi.org/10.1140/epja/s10050-023-00973-1
Regular Article –Theoretical Physics
The electromagnetic Sigma-to-Lambda transition form factors with coupled-channel effects in the space-like region
1
Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, 53115, Bonn, Germany
2
Technische Universität Darmstadt, Department of Physics, Institut für Kernphysik, 64289, Darmstadt, Germany
3
ExtreMe Matter Institute EMMI and Helmholtz Forschungsakademie Hessen für FAIR (HFHF), GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany
4
Institut für Kernphysik, Institute for Advanced Simulation and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425, Jülich, Germany
5
Tbilisi State University, 0186, Tbilisi, Georgia
Received:
4
May
2022
Accepted:
6
March
2023
Published online:
21
March
2023
Using dispersion theory, the electromagnetic Sigma-to-Lambda transition form factors are expressed as the product of the pion electromagnetic form factor and the 
scattering amplitudes with the latter estimated from SU(3) chiral perturbation theory including the baryon decuplet as explicit degrees of freedom. The contribution of the 
channel is also taken into account and the 
– coupled-channel effect is included by means of a two-channel Muskhelishvili–Omnès representation. It is found that the electric transition form factor shows a significant shift after the inclusion of the channel, while the magnetic transition form factor is only weakly affected. However, the effect on the electric form factor is obscured by the undetermined coupling 
in the three-flavor chiral Lagrangian. The error bands of the Sigma-to-Lambda transition form factors from the uncertainties of the couplings and low-energy constant in three-flavor chiral perturbation theory are estimated by a bootstrap sampling method.
© The Author(s) 2023
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