On the Gravitational Angular Momentum of Axial Perturbations of a Regular Black Hole

Abstract

This Letter deals with the gravitational angular momentum carried by axial (odd-parity) perturbations of the Bardeen regular black hole within the teleparallel equivalent of general relativity (TEGR). Using the Hamiltonian definition of conserved quantities in TEGR, we derive a closed expression for the perturbative angular momentum $δJ$ in terms of the axial perturbation function $h_0(r,t)$. The result exhibits a sharp multipolar selection rule: $δJ$ vanishes for odd values of the multipole index $\ell$, while even-$\ell$ modes yield a nonzero contribution. The radial and temporal behavior of $δJ$ is illustrated using the known axial quasinormal modes of the Bardeen spacetime.