Hidden gauge formalism for the radiative decays of axial-vector mesons

Abstract

The radiative decay of the axial-vector resonances into a pseudoscalar meson and a photon is studied using the vector meson Lagrangian obtained from the hidden gauge symmetry (HGS) formalism. The formalism is well suited to study this problem since it deals with pseudoscalar and vector mesons in a unified way, respecting chiral invariance. We show explicitly the gauge invariance of the set of diagrams that appear in the approach and evaluate the radiative decay width of the a1(1260) and b1(1235) axial vector meson resonances into pi gamma. We also include the contribution of loops involving anomalous couplings and compare the results to those obtained previously within another formalism.Comment: 24 pages, 6 tables, 11 figure

S-waveKK*interactions in a finite volume and thefGeng1, Ren2, Zhou3 et al. 2015Phys. Rev. D292330View full textAdd to dashboardCite

“…In recent years, however, it has been suggested to be a dynamically generated state made from the KK * interaction, together with its axial-vector counterparts [2,3]. Such a picture has been extensively tested in the past decade [4][5][6][7][8][9][10][11][12][13][14]. All these studies yield consistent results that the ground-state axial-vector mesons can be understood as dynamically generated states or at least contain large pseudoscalar meson-vector meson components.…”

The hidden-charm pentaquark and tetraquark states

“…Here, the first Lagrangian was constructed based on the hidden gauge interaction for vector mesons [279,280,281,282]; the third Lagrangian was introduced in Refs. [283,284,285,286,287] for the case of three flavors, and was extended to the case of four flavors in Refs.…”

Y(3940),Z(3930), and theXMolina1, Oset2 2009Phys. Rev. DSelf Cite

“…Some approximations were made there which make the formalism handy and reliable, by neglecting the three-momentum of the vector mesons with respect to their masses. It is interesting to see that with this approximation one obtains [39] from the hidden gauge approach the chiral local Lagrangians which are used to study the interaction of pseudoscalar mesons among themselves and the pseudoscalar mesons with vector mesons and with baryons [42,43,44,45]. …”

“…Our starting point is the Lagrangian, which involves the interaction of vector mesons amongst themselves, coming from the formalism of the hidden gauge symmetry (HGS) for vector mesons [31,32,39]…”