Faculty
Swift Discovery
An article recently published in Nature (vol 436, p. 985, 2005 Aug. 18) by a consortium including Peter Meszaros and colleagues from Penn State and several international institutions reports on a new result on cosmic gamma-ray bursts. This was obtained with the Swift scientific satellite, which is operated from Penn State. It shows that, following the prompt gamma-ray emission, the burst luminosity suffers a previously unsuspected, very steep decline, visible in the X-ray afterglow, which after an hour or so changes to a more gradual decline lasting for days.
More about the Swift Discovery.
Welcome to the Center for Particle Astrophysics!
The Center for Particle Astrophysics is engaged in a bold synergistic approach to understanding high energy processes in the universe. Our faculty at Penn State are prominent participants in three major international projects which make observations using extremely high energy protons, neutrinos and gamma-rays. These projects are, respectively, the Pierre Auger Cosmic Ray Observatory, the IceCube Neutrino Observatory and the Swift Gamma-Ray Burst Explorer satellite. Both Auger and IceCube are in advanced stages of construction and are poised to make major discoveries in the next few years. Penn State is the only U.S. institution participating in both of these premier ground-based projects of high energy particle astrophysics. Potentially observable sources for both Auger and IceCube include super-massive black holes at the center of active galaxies, and the explosive phenomena that give rise to gamma ray bursts (GRBs). These are believed to be especially violent supernova explosions and also mergers of collapsed stars in binary systems. Swift is presently providing the best gamma ray and X-ray observations of GRB explosions. Swift has been successfully operating for over three years, its mission control center being at Penn State. Penn State also plays a leading role in theoretical modeling of these explosions.
GRBs, and the mergers of super-massive black holes in the core of galaxies and quasars are also likely sources of detectable gravitational waves. Together with the Center for Gravitational Wave Physics, our Center will be studying GRBs and active galaxies by observing strong-interaction protons, weak-interaction neutrinos, electromagnetic gamma rays, and gravitational waves. Together, we cover all four forces of nature. This multi-force approach to high energy astrophysics is a pioneering venture in which the one-dimensional electromagnetic spectrum of conventional astronomy is supplemented with three other windows to the Universe. The discovery potential is enormous. Together with the Center for Fundamental Theory and the Institute for Gravitation and the Cosmos, the synergy between our various specialties and the breadth of knowledge to be gained through collaborations provide exciting prospects for making breakthroughs in our understanding of the Cosmos.