Challenges in X-ray binary timing: current and future

Details Challenges in X-ray binary timing: current and future Challenges in X-ray binary timing: current and future

Jan 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004adspr..34.2646v&link_type=abstract

Advances in Space Research, Volume 34, Issue 12, p. 2646-2656.

Astronomy and Astrophysics

Astrophysics

4

X-Ray Binary Timing, Astrophysics, Neutron Stars, Stellar-Mass Black Holes, X-Ray Binaries

Scientific paper

Millisecond X-ray time variability studies of accreting low-magnetic-field neutron stars and stellar-mass black holes in X-ray binaries probe the motion of matter in regions of strong gravity. In these regions, general relativity (GR) is no longer a small correction to the classical laws of motion, but instead dominates the dynamics: we are studying motion in strongly curved spacetime. Such millisecond X-ray variability studies can therefore provide unique tests of GR in the strong-field regime. The same studies also constrain neutron-star parameters such as stellar mass and radius, and thereby the equation of state (EOS) of ultradense matter. I briefly review the status, and discuss the prospects for mapping out space-time near accreting stellar-mass compact objects, and measuring the EOS of dense matter, through millisecond timing, particularly with an eye towards future missions. The overwhelming consideration for timing sensitivity is collecting area: contrary to most applications, the signal-to-noise ratio for the aperiodic timing phenomena produced by accretion flows increases proportionally with count rate rather than as the square root of it. A 10 times larger instrument turns 1σ effects into 10σ effects (or does as well in 1% of the time). With the Rossi X-ray Timing Explorer (RXTE), using 0.6 m2 collecting area, we have found several timing diagnostics from the accretion flow in the strong field region around neutron stars and black holes, as well as signals from neutron star surface hot spots. Combined work between RXTE and the new sensitive X-ray spectrographs onboard Chandra and XMM can already begin to clinch the geometry and physical mechanisms underlying these signals. Future instruments, larger in area by an order of magnitude and in some cases with enhanced spectral capabilities, are expected to turn these diagnostics of GR into true tests of GR. They are also expected to put strong constraints on neutron-star structure, and thereby on the EOS of supranuclear density matter.

Affiliated with

Also associated with

No associations

Rating

Challenges in X-ray binary timing: current and future does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Challenges in X-ray binary timing: current and future, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Challenges in X-ray binary timing: current and future will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1839285