Dilaton in a soft-wall holographic approach to mesons and baryons

Abstract

We discuss a holographic soft-wall model developed for the description of mesons and baryons with adjustable quantum numbers $n$, $J$, $L$, $S$. This approach is based on an action which describes hadrons with broken conformal invariance and which incorporates confinement through the presence of a background dilaton field. We show that in the case of the bound-state problem (hadronic mass spectrum) two versions of the model with a positive and negative dilaton profile are equivalent to each other by a special transformation of the bulk field. We also comment on recent works which discuss the dilaton sign in the context of soft-wall approaches.