First Adiabatic Invariant and the Brightness Temperature of Relativistic Jets

TL;DR

This paper explores how the conservation of the first adiabatic invariant in relativistic jets explains observed changes in brightness temperature along the jet, providing insights into jet physics.

Contribution

It introduces a model based on adiabatic invariant conservation to explain brightness temperature variations in relativistic jets.

Findings

The brightness temperature dependence on distance shows a characteristic break.

Conservation of the adiabatic invariant accounts for observed temperature changes.

The model aligns with observational data of relativistic jets.

Abstract

Assuming that the first adiabatic invariant for radiating particles in relativistic jets is conserved, we investigate the change in brightness temperature along the jet axis. We show that in this case the observed break in the dependence of the brightness temperature on the distance to the central engine can be explained.