Presentation 1 : Invited
MILLISECOND OSCILLATIONS IN LOW MASS X-RAY BINARIES (PCHE)
Jean-Francois Olive
Thanks to the Rossi X-ray Timing Explorer (RXTE), millisecond oscillations have finally been discovered from Low Mass X-ray Binaries containing low magnetic field neutron stars. In this talk, I briefly describe these new phenomena: the coherent oscillations during X-ray bursts and the kilo-Hertz Quasi-Periodic Oscillations in the persistent emission. The different models for these oscillations involve the neutron star rotation and the close orbital motion in the accretion disk around the neutron star. They rely explicitly on our understanding of the General Relativity in strong gravity fields and dense matter equation of state. I also present some simulations of burst oscillations observed with the next generation of timing instruments. Modeling the waveform of these oscillations could allow to measure precisely neutron star masses and radii for numerous accreting neutron stars to constrain the dense matter equation of state and, in particular, to test the strange star hypothesis.