Description of $Z+b\bar{b}$ with 4 flavour and 5 flavour transverse momentum dependent PDFs

We generate 4 flavour version of the NLO-PB PDFs by performing a fit to deep inelastic scattering (DIS) experimental data. 4 flavour Transverse Momentum Dependent (TMD) parton distribution functions (PDFs) calculated with the Parton Branching (PB) method are applied to predict two LHC processes: the transverse momentum spectrum of $Z$ boson and the azimuthal angular separation $\Delta\phi_{bb}$ between two $b$ jets in proton-proton collisions at a center-of-mass energy of 8 TeV.