Acceleration radiation, quasinormal modes and quasi-bound states in generic rotating regular black holes

Abstract

We study horizon-brightened acceleration radiation for a neutral scalar field in separable Kerr-like rotating metrics with nonlinear-electrodynamic mass profiles. The principal branch has $M=0$ and $μ=3$, with finite but direction-dependent central curvature limits. An analytic extremal charge--spin parametrization fixes the black hole domain. At a simple outer horizon, the scalar equation reduces to local conformal quantum mechanics with corotating energy $\epsh=ω-m\OmH$. For an isolated outgoing channel we derive the first finite-gap correction in proper time, including the radial Frobenius coefficient, angular variation, geodesic terms, and switching slope. This replaces a coordinate-dependent trajectory-phase multiplier by a protocol-defined detailed-balance affinity. Direct integration of the outgoing scalar equation and an equatorial infalling trajectory validates the expansion for an explicitly specified finite gate; a solvable logarithmic-mode limit separates switching from geometric contributions. We also analyze forced equatorial circular atoms and show that co-rotating and counter-rotating ultra-relativistic motion yields a mode-dependent orbital response rather than the infalling Hawking affinity. We identify the shrinking near-extremal radial scale and quantify the effect of an unselected second radial branch, without asserting a uniform extremal limit. Random atomic injection gives a selected-mode master equation and a nonnegative population entropy-production identity. A direct first-law integrability test shows why horizon-area bookkeeping remains conditional for this off-shell metric. Independently converged Chebyshev scalar quasinormal frequencies validate the WKB results and probe the exterior geometry beyond the leading horizon data. The calculation distinguishes branch-resolved horizon thermality, finite detector protocol, and exterior scalar dynamics.