Broken SU(6) symmetry and massive hybrid stars

In this work we revisit the quantum hadrodynamics (QHD) formalism to investigate hyperonic and hybrid stars with hyperon-meson couplings fixed via broken SU(6) group, in favor of a more general flavor group SU(3). This allows us to restrict a large number of free parameters to only one - the $\alpha_v$ - for the vector mesons, while the scalar meson can be constrained by the hyperon potential depth. We also employ an additional channel, the strangeness-hidden $\phi$ meson, which couples only to the hyperons and has a crucial role in the description of massive neutron stars. In hybrid stars, the quark phase is built with the SU(3) NJL model also with an additional vector channel in the Lagrangian, which enters as a free parameter within the limit imposed by the lattice QCD. We are able to reproduce 2.21 $M_\odot$ hyperonic star and 2.10 $M_\odot$ hybrid star. Both results are in agreement with the recently detected hyper massive pulsar MSP J0740+6620. With the models used in the present work, the minimum and the maximum masses of a hybrid star are very close to each other, indicating that if they exist, they are probably very rare in the universe.