NR simulations of PPI-unstable BH-disk systems: Effect of magnetization at late times*

Non-axisymmetric features in BH accretion disks are a sparsely-explored potential GW source. A natural channel for generating such features is the hydrodynamic Papaloizou-Pringle Instability (PPI). Previously, we conducted the first-ever study of the PPI around spinning BHs (a/M = 0.7), finding that BH spin can extend the signal lifetime and improve detection prospects by third-generation GW observatories. However, in a realistic scenario the material of these disks is likely to be magnetized. Prior studies have shown that the magneto-rotational instability (MRI) out-grows and surpresses the PPI during the early growth phase. Here we model a complementary scenario, where the PPI grows to its non-linear saturation state, and then the disk becomes magnetized in an MRI-suceptable configuration. This allows us to investigate, in full GR, a realistic non-axisymmetric configuration of magnetized matter which may concievably result from a number of formation channels. We find that the MRI once again attacks the non-axisymmetry and strongly reduces GW signal amplitude and lifetime.