Scalarization of slowly rotating black holes

It is interesting to note that most black holes are born very slowly rotating. We investigate scalarization of rotating in the Einstein-scalar-Chern-Simons (EsCS) theory. In slow rotation approximation, CS term takes a linear form parameter $a$ which determines tachyonic instability. The instability for represents onset spontaneous scalarization. shown unstable against spherically symmetric scalar-mode perturbation positive coupling $\alpha$, whereas these negative without any $a$-bound.