Previous abstract Next abstract
Session 24 - Invited Talk: Swank.
Oral session, Monday, June 08
The Rossi X-ray Timing Explorer has observed a wide range of sources and is producing valuable science. Its broad-band sensitivity has been key in the observations of both compact, stellar, and nebular objects.
RXTE is ideally suited for observing X-rays from both galactic and extragalactic black holes. The range of accretion rates, masses, and possibly angular momenta of stellar black hole candidates produce a variety of phenomena on which there are new results. Cygnus X-1 has temporal as well as spectral properties, sensitive to state transformations, which strongly constrain the physical picture for a whole class of sources. Quasi-periodic oscillations are characteristic of the microquasar GRS1915+105 and some are seen in other candidates. Coordinated observations have established the link betweeen accretion instabilities and emission in jets. Accretion onto the massive black holes in AGN also results in variations. These have inspired many observations of correlations with both gamma rays and long wavelengths.
Most neutron star X-ray sources are in low-mass binaries where relatively low magnetic fields allow accretion disks to persist where gravity is strong. With its high time resolution and large area RXTE is the only mission that can explore the domain of millisecond oscillations. Its measurements are providing evidence about the conditions at the neutron stars and determining spins, masses, and radii. In strong field accreting pulsars, quasi-periodic modulations may be diagnostic of the disk-magnetosphere interaction and the enigmatic spin behavior of some pulsars. RXTE recently discovered the fastest young rotation-powered pulsar. Among the special objects RXTE had the opportunity to observe are the bursting pulsar and the soft-gamma-ray repeater SGR1806-20.
RXTE's fast response was recently applied to the transient XTE J0421+56, which had an exceptionally fast rise and decay. This led to identification of corresponding radio and optical transients of the symbiotic star CI Cam.
Program listing for Monday