Sources of Gravitational Waves

During the twentieth century, the advent of radio astronomy, X-ray astronomy and optical astronomy from space have all led to major advances in the understanding of astronomical objects. The next frontier lies in the effort to detect gravitational waves and it is likely that within the next decade this new window on the Universe will be opened. Observing gravitational waves should give a much clearer view of compact objects (black holes and neutron stars), giving a better understanding of how they function and also allowing the possibility for investigating more thoroughly how matter and fields behave under these extreme conditions which it is not possible to reproduce in a terrestrial laboratory. Also, gravitational waves may give a way of investigating processes in the very early universe which are not observable by means of electromagnetic radiation.

Our group at SISSA is a participant in two major collaborations for studying sources of gravitational radiation: a European Union network collaboration  and the Italian collaboration OG51 of the INFN.

Main Projects:

• Oscillations of Relativistic Stars: Investigation of gravitational wave emission by neutron stars soon after their birth in supernovae, focussing particularly on the properties and behaviour of the CFS instability which may be an important source of gravitational waves.

 
• Gravitational Collapse of Rapidly Rotating Neutron Stars:We are studying in detail the process of formation of a Kerr black hole as a result of the collapse of a rapidly rotating neutron star. The careful investigation of the trapped surfaces produced during the collapse provides important information on the black hole properties (e.g. mass and spin) as well as an estimate on the amount on energy lost to gravitational waves.

 
• Coalescence of neutron star binaries: Studying both the inspiral phase and also the aftermath of the ensuing collision which may give rise to a black hole and an encircling ring of material at nearly nuclear matter density. Detailed computations are being made of these processes with the aim of predicting the gravitational waveforms which would be produced.

 
• Accretion Discs around Black Holes and Gravitational Wave Emission: Investigation of the high matter density torus expected to form around a rapidly rotating black hole after the coalescence of a neutron star binary system. Detailed study are being made of the accretion of matter onto the black hole and the emission of gravitational waves produced during this process.



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Staff Members: J.C. Miller, L. Rezzolla

Post-Docs: S. Karino

Ph.D. students: L. Baiotti, P. Montero

Main Collaborators: B. Ahmedov (Tashkent), Y. Eriguchi (Tokyo), V. Ferrari (Rome), T. Font (Valencia), I. Hawke (Potsdam), E. Seidel (Baton Rouge), N. Stergioulas (Thessaloniki), S. Yoshida (Milwaukee), O. Zanotti (Valencia).

Page created by:Luciano Rezzolla
Last change made: April 15, 2004