Nazgul is a framework for performing GRB localization via fitting non-parametric models to their data time-series and computing the the time delay between them. It is currentrly built upon the magic of Stan and implements a parallel version of non-stationary Random Fourier Features. The idea is get away from heuristic methods such as cross-correlation which do not have a self-consistent statitical model.

The idea is that satellites throughout the Sol system observe gamma-ray bursts at different times due to the finite speed of light. This creates a time delay in their observed light curves which can be used to triangulate the gamma-ray burst position on the sky. These triangulation create annuli or rings on the sky which Nazgul searchs for so that it, in the darkness, it can bind them to a location on the sky. (We are nerds, get over it).

The heriarchical model is shown below and details can be found in here. If you find the method and/or code useful in your research we ask that you please cite the paper.

The sister program to simulate time-delayed light curves is pyIPN and can be used to generate time-delayed light curves for algorithm testing.

This work is a joint effort by:

• J. Michael Burgess
• Ewan Cameron
• Dmitry Svinkin

pip install nazgul

Nazgul is still under heavy development! Expect problems!