Executive Summary : | Gamma ray bursts (GRBs) are intense flashes of gamma rays produced by the death of massive stars or merger of binary compact objects like binary neutron stars or neutron star-black holes. Since their discovery in 1967, GRBs have been elusive in terms of their origin, jet outflow composition, and dynamics. High energy gamma ray space observatories focus on understanding the underlying mechanism of radiation. As observations and studies increase, complex theoretical emission models have emerged, including more realistic jet dynamics. This has led to degenerate and ambiguous interpretations within simple phenomenological models. One key way forward is to directly test physical models with observations and assess the physical implications of the obtained fit results. The sub-photospheric dissipation model is one of the competing emission models in GRBs, which we aim to test with data. The direct physical model testing technique involves generating a finer grid of spectral shapes for different combinations of free parameters, which is then used to find the best fit parameters when tested against data using robust statistical analysis techniques. The hydrodynamic simulations involving the evolution of a relativistic jet through stellar matter will provide insights into the temporal dynamics of jets during burst duration. Additionally, studies can help us understand the properties of the progenitor massive star. Our research work involves analyzing large amounts of observational astronomical data, developing and utilizing various machine learning and artificial intelligence algorithms, and implementing different investigation techniques to study various aspects of GRB physics. |