Vector transition form factors of the [formula omitted] and [formula omitted] in the [formula omitted] chiral quark–soliton model

Abstract

We investigate the vector transition form factors of the nucleon and vector meson K ∗ to the pentaquark baryon Θ + within the framework of the SU ( 3 ) chiral quark–soliton model. We take into account the rotational 1 / N c and linear m s corrections, assuming isospin symmetry and employing the symmetry-conserving quantization. It turns out that the leading-order contributions to the form factors are almost cancelled by the rotational corrections. Because of this, the flavor SU ( 3 ) symmetry-breaking terms yield sizeable effects on the vector transition form factors. In particular, the main contribution to the electric-like transition form factor comes from the wave-function corrections, which is a consequence of the generalized Ademollo–Gatto theorem derived in the present work. We estimate with the help of the vector meson dominance the K ∗ vector and tensor coupling constants for the Θ + : g K ∗ N Θ = 0.74 – 0.87 and f K ∗ N Θ = 0.53 – 1.16 . We argue that the outcome of the present work is consistent with the null results of the CLAS experiments in the reactions γ n → K − Θ + and γ p → K ¯ 0 Θ + . The results of the present work are also consistent with the recent experiments at KEK. In addition, we present the results of the Σ 10 ¯ → N K ¯ ∗ transition form factors and its K ¯ ∗ N Σ 10 ¯ coupling constants.