Coherent Emission in Fast Radio Bursts

Understand

The fast (ms) radio bursts reported by Thornton, {\it et al.} have extremely high brightness temperatures if at the inferred cosmological distances.

• This implies coherent emission by "bunches" of charges.
• We model the emission region as a screen of dipole radiators resonant at the frequency of observation and calculate the necessary charge bunching.
• From this we infer the minimum electron energy required to overcome electrostatic repulsion.