Journal Article

Photon-fusion reactions from the chiral Lagrangian with dynamical light vector mesons

Danilkin, I. V., Terschlüsen, C., Lutz, M. F. M., Leupold, S.

2013

Overview

We study the reactions γγ → π 0 π 0 , π + π − , , K + K − , ηη and π 0 η based on a chiral Lagrangian with dynamical light vector mesons as formulated within the hadrogenesis conjecture. At present our chiral Lagrangian contains five unknown parameters that are relevant for the photon-fusion reactions. They parameterize the strength of interaction terms involving two vector meson fields. These parameters are fitted to photon-fusion data γγ → π 0 π 0 , π + π − , π 0 η and to the decay η → π 0 γγ . In order to derive gauge invariant reaction amplitudes in the resonance region constraints from maximal analyticity and exact coupled-channel unitarity are used. Our results are in good agreement with the existing experimental data from threshold up to about 0.9 GeV for the two-pion final states. The a 0 meson in the π 0 η channel is dynamically generated and an accurate reproduction of the γγ → π 0 η data is achieved up to 1.2 GeV. Based on our parameter sets we predict the γγ → , K + K − , ηη cross sections.

• Publisher: Springer-Verlag,Springer Nature B.V
• Subject: Astronomy / Astrophysics and Cosmology / Channels / Chiral Lagrangians / Cross sections / Dispersion relations / Elementary Particles / Hadrons / Heavy Ions / Invariants / Joining / Mathematical analysis / Measurement Science and Instrumentation / Meson production / Nuclear Energy / Nuclear Physics / Partial-wave analysis / Physics / Physics and Astronomy / Quantum Field Theories / Quantum Field Theory / Regular Article - Theoretical Physics / Reproduction / String Theory / Vector mesons / Vector-meson dominance