THE THREE HUNDRED project: The GIZMO-SIMBA run

We introduce GIZMO-SIMBA, a new suite of galaxy cluster simulations within THE THREE HUNDRED project. THE THREE IIUNDRED consists of zoom re-simulations of 324 clusters with M-200 greater than or similar to 10(14.8) M-circle dot drawn from the MultiDark-Planck N-body simulation, run using several hydrodynamic and semi-analytical codes. The GIZMO-SIMBA suite adds a state-of-the-art galaxy formation model based on the highly successful SIMBA simulation, mildly re-calibrated to match z = 0 cluster stellar properties. Comparing to THE THREE HUNDRED zooms run with GADGET-X, we find intrinsic differences in the evolution of the stellar and gas mass fractions, BCG ages, and galaxy colour-magnitude diagrams, with GIZMO-SIMBA generally providing a good match to available data at z approximate to 0. GIZMO-SIMBA'S unique black hole growth and feedback model yields agreement with the observed BH scaling relations at the intermediate-mass range and predicts a slightly different slope at high masses where few observations currently lie. GIZMO-SIMBA provides a new and novel platform to elucidate the co-evolution of galaxies, gas, and black holes within the densest cosmic environments.