Astrophysics & Particle Physics-APPC 2026

Gamma-Ray Bursts (GRBs) are the most powerful electromagnetic bursts in the universe, releasing copious gamma radiation for milliseconds to a few minutes. They are seen at cosmological distances and are connected with some of the most violent astrophysical phenomena.GRBs are divided into long and short bursts depending on their duration. Long GRBs (longer than 2 seconds) are usually associated with the collapse of massive stars into black holes, sometimes with supernovae. Short GRBs (shorter than 2 seconds) are due mainly to neutron star-neutron star or neutron star-black hole mergers, processes which can also release kilonovae.

These bursts have relativistic jets, tightly collimated beams of particles traveling at almost the speed of light. Study of the afterglow of GRBs at various wavelengths—X-ray, optical, infrared, and radio—allows astronomers to examine the structure of the jet, energetics, and the ambient medium.Astronomers rely on space-based gamma-ray observatories such as Swift, Fermi, and INTEGRAL to detect GRBs and offer rapid notification for follow-up observations. Multi-messenger observations, such as gravitational waves, have enabled accurate identification of progenitors for short GRBs and connecting them to neutron star mergers.GRBs give valuable information on stellar evolution, black hole formation, and high-energy astrophysics. GRBs also serve as cosmic probes for the study of the intergalactic medium, the formation of galaxies, and chemical enrichment at high redshifts.Gamma-ray bursts are used by scientists to examine extreme physics, such as relativistic shocks, magnetic field interactions, and particle acceleration mechanisms. GRBs hold the secret to the violent evolution constructing the universe and are cosmic laboratories for the study of high-energy phenomena inaccessible to laboratory experiments on Earth.