大样本恒星演化研究组知识库

The Blandford-Znajek (BZ) mechanism describes a process for extracting the rotation energy from a spinning black hole (BH) via magnetic field lines penetrating the event horizon of the central BH. In this paper, we present a perturbation approach to study force-free jets launched by the BZ mechanism, and then discuss its two immediate applications: (1) we present a high-order split-monopole perturbation solution to the BZ mechanism which accurately pins down the energy extraction rate E. and well describes the structure of the BH magnetosphere for the entire range of BH spins (0 <= a <= 1); (2) the approach yields an exact constraint for the monopole field configuration in Kerr spacetime, I = Omega(1-A(phi)(2)), where A(phi) is the phi component of the vector potential of electromagnetic field, Omega is the angular velocity of the magnetic field lines, and I is the poloidal electric current. The constraint is of particular importance to benchmark the accuracy of numerical simulations.