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arXiv · 0706.1543

Structure of Vector Mesons in Holographic Model with Linear Confinement

H. R. Grigoryan·A. V. Radyushkin
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Abstract

Wave functions and form factors of vector mesons are investigated in the holographic dual model of QCD with a smooth oscillator-like wall. We introduce wave functions conjugate to solutions of the 5D equation of motion and develop a formalism based on these wave functions, which are very similar to those of a quantum-mechanical oscillator. For the lowest bound state (rho-meson), we show that, in this model, the basic elastic form factor exhibits the perfect vector meson dominance, i.e., it is given by the rho-pole contribution alone. The electric radius of the rho-meson is calculated, _C = 0.655 fm^2, which is larger than in case of the hard-wall cutoff. The squared radii of higher excited states are found to increase logarithmically rather than linearly with the radial excitation number. We calculate the coupling constant f_rho and find that the experimental value is closer to that calculated in the hard-wall model.

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H. R. Grigoryan, A. V. Radyushkin. 2007-10-11. Structure of Vector Mesons in Holographic Model with Linear Confinement. https://doi.org/10.1103/physrevd.76.095007

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