A kiloparsec-scale internal shock collision in the jet of a nearby radio galaxy

摘要: Observations of a collision between two knots in the jet nearby radio galaxy 3C 264 support internal shock model how plasma is energized. Using twenty-year dataset Hubble Space Telescope images, Eileen Meyer et al. have tracked motion high-energy produced by super-massive black hole galaxy. The authors find that one bright 'knot' has been catching up with slower-moving knot just downstream. Images taken 2014 record first stages their inevitable collision. Colliding long theorized as capable accelerating particles produce radiation many astrophysical jets, mechanism known 'internal model', but this time such observed. Jets highly energized relativistic velocities are associated holes ranging mass from few times Sun to billion-solar-mass at centres galaxies1. A popular unconfirmed hypothesis explain ‘internal model’, which flow unsteady2. Faster components catch and collide slower ones, leading shocks accelerate generate magnetic fields3. This can variable, emission diverse set objects4,5,6,7, best indirect evidence being unseen fast inferred energize X-ray binary jets8,9. Mapping kinematic profiles resolved jets revealed precessing helical patterns binaries10,11, apparent superluminal motions12,13, ejection (bright components) standing active galaxies14,15. revealing structure evolution an action have, however, remained elusive, hindering measurement physical parameters ultimate efficiency mechanism. Here we report observations 264. speed (7.0 ± 0.8)c, where c light vacuum, incipient (1.8 0.5)c downstream, resulting brightening both knots—as seen most recent epoch imaging.