  The calculations of $Z + b{\bar b}$ tagged jet production performed in the
four- and five-flavour schemes allow for detailed comparison of the heavy
flavour structure of collinear and transverse momentum dependent (TMD) parton
distributions as well as for detailed investigations of heavy quarks radiated
during the initial state parton shower cascade.
  We have determined the first set of collinear and TMD parton distributions in
the four-flavour scheme with NLO DGLAP splitting functions within the
Parton-Branching (PB) approach. The four- and five-flavour PB-TMD distributions
were used to calculate $Z + b{\bar b}$ tagged jet production at LHC energies
and very good agreement with measurements obtained at $\sqrt{s} = 8, 13 $ TeV
by the CMS and ATLAS collaborations is observed.
  The different configurations of the hard process in the four- and
five-flavour schemes allow for a detailed investigation of the performance of
heavy flavor collinear and TMD parton distributions and the corresponding
initial TMD parton shower, giving confidence in the evolution of the PB-TMD
parton densities as well as in the PB-TMD parton shower.
