Black Hole Jet Models with Anisotropic Nonthermal Electrons and Slow-Light Radiative Transfer

State-of-the-art very-long-baseline interferometry (VLBI) observations provide essential clues to the magnetically driven mechanism of active galactic nucleus jets from supermassive black holes. Meanwhile, theoretical models have struggled to reproduce the limb-brightened structures that are widely observed in the jets. To address this discrepancy, we introduce an anisotropic nonthermal synchrotron-electron model based on insights from plasma particle physics. We combine this model with general relativistic magnetohydrodynamics (GRMHD) simulations and perform “slow-light” radiative transfer calculations, which account for the time evolution of plasma while light rays propagate through it, to produce theoretical images of the M87 jet. As a result, we find that anisotropic emission globally reproduces the limb-brightening structure. We also show that the intrinsically helical jet structure in GRMHD appears stretched and smoothed out into a conical morphology in the images by the slow-light effect, and that the black hole spin and magnetic-field geometry are imprinted in the transition from a helical to a conical structure. These results suggest that a combined framework of plasma particle physics, fluid dynamics, and radiative transfer can shed new light on the century-long-standing problem of jet formation through comparisons with next-generation observations.