Holographic Baryons - Static Properties and Form Factors from Gauge/String Duality

In this paper, we study the properties of baryons by using a holographic dual of QCD on the basis of the D4/D8-brane configuration, where baryons are described by a soliton. We first determine the asymptotic behavior of the soliton solution, which allows us to evaluate well-defined currents associated with the Y(N-f)(L) x U(N-f)(R) chiral symmetry. Using the currents. we compute the static quantities of baryons such as charge radii and magnetic moments, and perform a quantitative comparison with experiments. It is emphasized that not only the nucleon but also excited baryons, such as Delta, N(1440), N(1535), etc., can be analyzed systematically in this model. We also investigate the form factors and find that our form factors agree well with the results that have been well established empirically. Using the form factors, the effective baryon-baryon-meson cubic coupling constants among their infinite towers in the model can be determined. Some physical implications following from these results are discussed.