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arXiv · 2009.08350

nazgul: A statistical approach to gamma-ray burst localization. Triangulation via non-stationary time-series models

J. Michael Burgess·Ewan Cameron·Dmitry Svinkin·Jochen Greiner
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Abstract

Context. Gamma-ray bursts can be located via arrival time signal triangulation using gamma-ray detectors in orbit throughout the solar system. The classical approach based on cross-correlations of binned light curves ignores the Poisson nature of the time-series data, and is unable to model the full complexity of the problem. Aims. To present a statistically proper and robust GRB timing/triangulation algorithm as a modern update to the original procedures used for the Interplanetary Network (IPN). Methods. A hierarchical Bayesian forward model for the unknown temporal signal evolution is learned via random Fourier features (RFF) and fitted to each detector's time-series data with time-differences that correspond to GRB's position on the sky via the appropriate Poisson likelihood. Results. Our novel method can robustly estimate the position of a GRB as verified via simulations. The uncertainties generated by the method are robust and in many cases more precise compared to the classical method. Thus, we have a method that can become a valuable tool for gravitational wave follow-up. All software and analysis scripts are made publicly available here (https://github.com/grburgess/nazgul) for the purpose of replication.

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J. Michael Burgess, Ewan Cameron, Dmitry Svinkin, Jochen Greiner. 2020-09-17. nazgul: A statistical approach to gamma-ray burst localization. Triangulation via non-stationary time-series models. https://doi.org/10.1051/0004-6361/202039461

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