Priors on Lagrangian bias parameters from galaxy formation modelling
  We study the relations among the parameters of the hybrid Lagrangian bias
expansion model, fitting biased auto and cross power spectra up to $k_{\rm max}
= 0.7 \, h \, \mathrm{Mpc}^{-1}$. We consider $\sim 8000$ halo and galaxy
samples, with different halo masses, redshifts, galaxy number densities, and
varying the parameters of the galaxy formation model. Galaxy samples are
obtained through state-of-the-art extended subhalo abundance matching
techniques and include both stellar-mass and star-formation-rate selected
galaxies. All of these synthetic galaxies samples are publicly available at
https://bacco.dipc.org/galpk.html. We find that the hybrid Lagrangian bias
model provides accurate fits to all of our halo and galaxy samples. The
coevolution relations between galaxy bias parameters, although roughly
compatible with those obtained for haloes, show systematic shifts and larger
scatter. We explore possible sources of this difference in terms of dependence
on halo occupation and assembly bias of each sample. The bias parameter
relations displayed in this work can be used as a prior for future Bayesian
analyses employing the hybrid Lagrangian bias expansion model.
