- SAX J1808.4-3658
A transient X-ray source first discovered in 1996 by the Italian-Dutch
BeppoSAXsatellite, SAX J1808.4-3658 revealed X-ray pulsations at the 401 Hz neutron star spin frequency when it was observed during a subsequent outburst in 1998 by NASA's RXTE satellite. The neutron starorbits a brown dwarfbinary companion with a likely mass of 0.05 solar masses, every 2.01 hours. X-ray burst oscillations and quasi-periodic oscillations in addition to coherent X-ray pulsations have been seen from SAX J1808.4-3658, making it a Rosetta stone for interpretation of the timing behavior of low-mass X-ray binaries.
These accreting millisecond X-ray
pulsars are thought to be the evolutionary progenitors of recycled radio millisecond pulsars. A total of ten accreting millisecond X-ray pulsars have been discovered as of October 2007. Three of them are Intermittent millisecond X-ray pulsars (HETE J1900.1-2455, Aql X-1 and SAX J1748.9-2021), i.e. they emit pulsations sporadically during the outburst.
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См. также в других словарях:
Pulsar — Pulsars are highly magnetized rotating neutron stars that emit a beam of electromagnetic radiation in the form of radio waves. Their observed periods range from 1.4 ms to 8.5 s. [ M.D. Young, R.N. Manchester and S. Johnston. A radio pulsar with… … Wikipedia
RXTE — Rossi X ray Timing Explorer Обсерватория RXTE в представлении художника (рисунок NASA) Организация … Википедия