FRB Detection

Status: Mature

Introduction

Fast Radio Bursts (FRB) are short-time, non-periodic, wideband pulse signals coming from the sky with an unknown origin that have caught a great interest from astronomers in recent years. Detecting them is a real challenge because of their short duration and apparent random time and location. They are usually 'discovered' in sorted data much latter in measurements with a different purpose.

In this project a real-time FRB detector implemented in ROACH2 is proposed. The purpose of the detector is to produce an alarm the moment an FRB is detected, and store the raw data of that exact moment. This way, FRB data can be analyzed opportunely, and detection can be achieved when the telescope is making observations for an unrelated topic. The detector is based in a technique called incoherent dedispersion, which means that the detector must reverse the effect of the intergalactic plasma, that disperse the FRB signal, delaying lower frequencies components more that higher frequencies. By applying those delays in reverse order in the frequency domain, one can retrieve the original high bandwidth signal, and apply a signal power threshold to indicate a detection.

Documentation

Wiki article for FRBs: https://en.wikipedia.org/wiki/Fast_radio_burst
Dispersion formula for inerstellar/intergalactic plasma: https://casper.ssl.berkeley.edu/astrobaki/index.php/Dispersion_measure
FRB Catalog: http://frbcat.org/ / https://arxiv.org/abs/1601.03547
Paper about FRB (or other transient) detection:
Thesis with techniques that also has good theory explanation: https://arxiv.org/abs/1109.0416
Sergio's thesis on the implementation of FRB detector in ROACH2: http://repositorio.uchile.cl/handle/2250/177139

Code and Models

ROACH2 FRB detector models, bofs, and script examples: https://github.com/FrancoCalan/simulink_models/tree/master/FRB_Detection/ROACH2