The high-energy astrophysics group studies accretion-powered high-energy sources such as neutron
stars and black holes as well as gamma-ray bursts. Our strength is the combination of
observational and theoretical research. We are actively involved in the analysis of the
data on accreting black holes (stellar-mass and supermassive), ultraluminous X-ray sources and accreting millisecond
pulsars obtained with the X-ray and gamma-ray observatories RXTE, XMM-Newton,
INTEGRAL, and Fermi. We also develop theoretical models for boundary layers around neutron stars and
super-Eddington accretion disks around black holes. We have pioneered theoretical
modelling of the light curves from rapidly rotating neutron stars and have developed
state-of-the-art computer code for modelling the radiative processes in relativistic
plasmas. We have proposed a novel particle
acceleration mechanism-"photon breeding"-operating is relativistic jets emanating from
active galactic nuclei. We have discovered that the breaks observed at a few GeV by Fermi
in powerful blazars are produced by photon-photon annihilation on He II Lyman continuum,
prooving thus for the first time that the blazar gamma-ray emitting region lies within
high-ionization zone of the broad-line region.
Introduction to the high energy astrophysics can be found here in English or
here in Finnish.
Group meetings take place on Wednesdays, 14.00 in the
3rd floor coffee room.
The group leader is professor Juri
Department of Physical Sciences
P.O. Box 3000
90014 University of Oulu