Long-Lived Positronium and AGN Jets

Figure 1

A positronium atom is oriented in the 𝑥-𝑦 plane, moving parallel to the axis of the jet. As the system evolves in time, both ^→𝑟 and ^→𝜋 change direction, but ^→𝜅  is a constant of motion. The magnetic field is dominated by the azimuthal component, ^→𝐵=𝐵𝜙.