The electromagnetic Sigma-to-Lambda hyperon transition form factors at low energies

Abstract

Using dispersion theory the low-energy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the two-pion--Sigma--Lambda amplitudes are determined from relativistic next-to-leading-order (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole low-energy region. The magnetic transition form factor depends strongly on one not very well determined low-energy constant of the NLO Lagrangian. One obtains reasonable predictive power if this low-energy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR).

18 pages

References in corpus (11)

• The pion-pion scattering amplitude. IV: Improved analysis with once subtracted Roy-like equations up to 1100 MeV
• Electromagnetic excitation of the Delta(1232)-resonance
• The Proton Radius Puzzle
• Dispersive analysis of omega --> 3pi and phi --> 3pi decays
• Dispersive analysis of the pion transition form factor
• On the pi pi continuum in the nucleon form factors and the proton radius puzzle
• Dispersive analysis of the scalar form factor of the nucleon
• Octet-baryon axial-vector charges and SU(3)-breaking effects in the semileptonic hyperon decays
• On the chiral effective meson-baryon Lagrangian at third order
• Consistency of the $\pi \Delta$ interaction in chiral perturbation theory
• Measurement of the pi^0 -> e^+e^-gamma Dalitz decay at the Mainz Microtron

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