TY - JOUR

T1 - Gauge invariant formulation of 3γ decay of particle-antiparticle bound states

AU - Blankleider, Boris

AU - Kvinikhidze, Alexander

AU - Silagadze, Z

PY - 2015/8/26

Y1 - 2015/8/26

N2 - We construct the gauge invariant three-photon decay amplitude of particle-antiparticle bound states modeled by the Dyson-Schwinger and Bethe-Salpeter equations. Application to the quark-antiquark (qq¯) bound states is emphasized. An essential aspect of our formulation is that it applies to any underlying quantum field theoretic model of the qq¯ system, and not just to models, like exact QCD, where the quark self-energy Σ couples to the electromagnetic field solely via dressed quark propagators. In this way, applications to effective field theories and other QCD motivated models are envisioned. The three-photon decay amplitude is constructed by attaching currents to all possible places in the Feynman diagrams contributing to the dressed quark propagator. The gauge invariance of our construction is thus a direct consequence of respecting the underlying structure of the quantum field theory determining the dynamics. In the resultant expression for the three-photon decay amplitude, all the basic ingredients consisting of the bound-state wave function, the final-state interaction qq¯ t matrix, the dressed quark propagator, and dressed quark currents, are determined by a universal Bethe-Salpeter kernel.

AB - We construct the gauge invariant three-photon decay amplitude of particle-antiparticle bound states modeled by the Dyson-Schwinger and Bethe-Salpeter equations. Application to the quark-antiquark (qq¯) bound states is emphasized. An essential aspect of our formulation is that it applies to any underlying quantum field theoretic model of the qq¯ system, and not just to models, like exact QCD, where the quark self-energy Σ couples to the electromagnetic field solely via dressed quark propagators. In this way, applications to effective field theories and other QCD motivated models are envisioned. The three-photon decay amplitude is constructed by attaching currents to all possible places in the Feynman diagrams contributing to the dressed quark propagator. The gauge invariance of our construction is thus a direct consequence of respecting the underlying structure of the quantum field theory determining the dynamics. In the resultant expression for the three-photon decay amplitude, all the basic ingredients consisting of the bound-state wave function, the final-state interaction qq¯ t matrix, the dressed quark propagator, and dressed quark currents, are determined by a universal Bethe-Salpeter kernel.

UR - http://www.scopus.com/inward/record.url?scp=84940870312&partnerID=8YFLogxK

U2 - 10.1103/PhysRevD.92.045032

DO - 10.1103/PhysRevD.92.045032

M3 - Article

VL - 92

SP - 045032-1-045032-20

JO - Physical Review D

JF - Physical Review D

SN - 1089-4918

IS - 4

M1 - 045032

ER -