Synchrotron masers and fast radio bursts

Understand

Fast Radio Bursts (FRBs), with a typical duration of 1 ms and 1 Jy flux density at GHz frequencies, have brightness temperatures exceeding 1e33 K, requiring a coherent emission process.

• This can be achieved by bunching particles in volumes smaller than the typical wavelength, but this may be challenging.
• Alternatively, we can have maser emission.
• Under certain conditions, the synchrotron stimulated emission process can be more important than true absorption, and a synchrotron maser can be created.