Heavy baryons and their exotics from instantons in holographic QCD
Phys. Rev. D 95, 116012 – Published 23 June, 2017
DOI: https://doi.org/10.1103/PhysRevD.95.116012
Abstract
We use a variant of the construction that includes two chiral and one heavy meson, to describe heavy-light baryons and their exotics as heavy mesons bound to a flavor instanton in bulk. At strong coupling, the heavy meson is shown to always bind in the form of a flavor instanton zero mode in the fundamental representation. The ensuing instanton moduli for the heavy baryons exhibits both chiral and heavy quark symmetry. We detail how to quantize it, and derive model independent mass relations for heavy baryons with a single-heavy quark in leading order, in overall agreement with the reported baryonic spectra with one charm or bottom. We also discuss the low-lying masses and quantum assignments for the even and odd parity states, some of which are yet to be observed. We extend our analysis to double-heavy pentaquarks with hidden charm and bottom. In leading order, we find a pair of double-heavy iso-doublets with assignments for all heavy flavor combinations. We also predict five new Delta-like pentaquark states with assignments for both charm and bottom.