Extreme Astrophysics

What are the laws of physics governing black holes, neutron stars, and relativistic plasmas in the strongest gravitational and magnetic fields in nature? How do compact objects launch jets, accelerate particles, and produce the high-energy emission we see from pulsars, supernova remnants, and active galactic nuclei? How can we combine electromagnetic observations with gravitational waves to reveal what happens near event horizons and to probe dense matter, strong-field gravity, and extreme particle acceleration? And how do black holes grow and influence their environments across cosmic time—from stellar explosions to galaxy evolution?

At KIPAC, we investigate the most extreme phenomena in the Universe by combining theory, simulation, observation, and instrumentation across multiple messengers. We develop analytic and computational models of relativistic plasmas and compact objects, analyze high-energy and time-domain data, and use multi-messenger measurements—such as gravitational waves—together with electromagnetic surveys to search for signatures of new physics and to understand how black holes and neutron stars shape their cosmic environments.

Extreme astrophysics connects fundamental physics to the most energetic events in the cosmos. Compact objects—black holes and neutron stars—create laboratories for strong-field gravity, ultra-dense matter, and relativistic plasmas, producing jets, high-energy radiation, and bursts that can be observed across the electromagnetic spectrum. Today, these sources are increasingly studied through multiple messengers: light, particles, and gravitational waves. Together, these observations let us model how matter behaves under extreme conditions and use the Universe as a testbed for physics that cannot be reproduced on Earth.

Black Holes

KIPAC researchers study black holes across mass scales—from stellar-mass black holes in X-ray binaries to supermassive black holes in active galactic nuclei and quasars—to understand how they accrete matter, power intense high-energy emission, and launch relativistic jets. We combine multiwavelength observations (radio through gamma rays) with analytic theory and numerical simulations of relativistic plasmas to connect observed radiation and variability to the physical conditions near event horizons. This work sheds light on how black holes grow over cosmic time and how black hole feedback shapes galaxies and the environments in which they live.

Compact Objects: Neutron stars and Pulsars

KIPAC researchers study the compact remnants of stellar evolution—white dwarfs, neutron stars, and pulsars—to probe matter at extreme densities, strong gravity, and ultra-strong magnetic fields. By combining theoretical models with observations across the electromagnetic spectrum, we connect pulsar emission, magnetospheric physics, and transient behavior to the underlying plasma processes  and particle acceleration that power their high-energy emission. When compact objects merge or undergo violent outbursts, multi-messenger measurements—especially gravitational waves alongside electromagnetic counterparts—provide new ways to test dense-matter physics and strong-field gravity.

Multi-messenger Astrophysics

Extreme events often reveal themselves through more than one messenger. KIPAC researchers combine electromagnetic observations with gravitational-wave measurements to study compact-object mergers and other transients, connecting source populations and environments to the physics of strong gravity and dense matter. These multi-messenger datasets also provide new opportunities to test cosmology and fundamental physics using astrophysical sources.

Particle Acceleration

The Universe is filled with particles accelerated to near light speed, but where and how this acceleration occurs remains a central question in high-energy astrophysics. KIPAC researchers study particle acceleration in sources such as pulsars, supernova remnants, and active galactic nuclei by combining theory and simulations with gamma-ray observations from space-based instruments such as the Fermi Large Area Telescope and from the ground with Cherenkov telescopes that detect atmospheric air showers. These measurements connect high-energy emission to the physical mechanisms—shocks, magnetic reconnection, and relativistic outflows—that power cosmic particle accelerators. We also explore how populations of high-energy sources shape the cosmic gamma-ray sky and what they reveal about particle transport and radiation processes.