  In this analysis, the so-called holographic graviton soft-wall model (GSW),
first developed to investigate the glueball spectrum, has been adopted to
predict the masses of hybrids with different quantum numbers. Results have been
compared with other models and lattice calculations. We have extended the GSW
model by introducing two modifications based on anomalous dimensions in order
to improve our agreement with other calculations and to remove the initial
degeneracy not accounted for by lattice predictions. These modifications do not
involve new parameters. The next step has been to identify which of our
calculated states agree with the PDG data, leading to experimental hybrids. The
procedure has been extended to include hybrids made of heavy quarks by
incorporating the quark masses into the model.
