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arXiv · 2409.16852

Multi-physics framework for fast modeling of gamma-ray burst afterglows

Vsevolod Nedora·Ludovica Crosato Menegazzi·Enrico Peretti·Tim Dietrich·Masaru Shibata
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Abstract

In this paper, we present PyBlastAfterglow, a modular C++ code with a Python interface to model light curves and sky maps of gamma-ray burst afterglows. The code is open-source, modular, and sufficiently fast to perform parameter grid studies. PyBlastAfterglow is designed to be easily extendable and used as a testing bed for new physics and methods related to gamma-ray burst afterglows. For the dynamical evolution of relativistic ejecta, a thin-shell approximation is adopted, where both forward and reverse shocks are included self-consistently, as well as lateral structure, lateral spreading, and radiation losses. Several models of the shock microphysics are implemented, including a fully numerical model of the downstream electron distribution evolution, synchrotron emission, self-absorption, and synchrotron self-Compton emission under the one-zone approximation. Thus, the code is designed to be able to model complex afterglows that include emission from reverse shock, very high energy emission, structured jets, and off-axis observations.

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Vsevolod Nedora, Ludovica Crosato Menegazzi, Enrico Peretti, Tim Dietrich, Masaru Shibata. 2024-09-25. Multi-physics framework for fast modeling of gamma-ray burst afterglows. https://arxiv.org/abs/2409.16852

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