Compact objects, celestial bodies characterized by very strong gravity such as neutron stars, pulsars and black holes, are subjects of intense research at KIPAC. KIPAC scientists study these various compact objects using data from the Fermi Gamma-ray Space Telescope. The gamma-ray emissions from pulsars allow researchers to study how their intense, pulsed radiation is produced. Researchers now believe that pulsars behave like powerful magnets in which the poles are not aligned with the axis of the star's rotation. The energetic particles emanating from a pulsar form a beacon — similar to the beam of the lighthouse — which periodically sweeps across our line of sight once or twice per revolution. By taking an accurate count of pulsars, KIPAC scientists have been able to estimate how often stellar collapses take place in the Milky Way.
Developing Complex Models
In addition to neutron stars and pulsars, the Fermi telescope has detected hundreds of black holes with powerful jets. To get a better idea of the structure of these jets and hone in on the nature of the radiating particles, KIPAC scientists are using the Fermi data as well as observations in the radio, visible, and X-ray bands to build computer models. The models are complex but KIPAC scientists have been among the very first to accurately describe the twisted magnetic field that occurs when matter falls into a black hole and deduce how the field determines the precise alignment of the jet.