A Bayesian Inference Framework for Gamma-ray Burst Afterglow Properties

In the field of multi-messenger astronomy, Bayesian inference is commonly adopted to compare the compatibility of models given the observed data. However, to describe a physical system like neutron star mergers and their associated gamma-ray burst (GRB) events, usually more than ten physical paramet...

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Bibliographic Details
Main Authors: En-Tzu Lin, Fergus Hayes, Gavin P. Lamb, Ik Siong Heng, Albert K. H. Kong, Michael J. Williams, Surojit Saha, John Veitch
Format: Article
Language:English
Published: MDPI AG 2021-09-01
Series:Universe
Subjects:
Online Access:https://www.mdpi.com/2218-1997/7/9/349
Description
Summary:In the field of multi-messenger astronomy, Bayesian inference is commonly adopted to compare the compatibility of models given the observed data. However, to describe a physical system like neutron star mergers and their associated gamma-ray burst (GRB) events, usually more than ten physical parameters are incorporated in the model. With such a complex model, likelihood evaluation for each Monte Carlo sampling point becomes a massive task and requires a significant amount of computational power. In this work, we perform quick parameter estimation on simulated GRB X-ray light curves using an interpolated physical GRB model. This is achieved by generating a grid of GRB afterglow light curves across the parameter space and replacing the likelihood with a simple interpolation function in the high-dimensional grid that stores all light curves. This framework, compared to the original method, leads to a ∼90× speedup per likelihood estimation. It will allow us to explore different jet models and enable fast model comparison in the future.
ISSN:2218-1997