X-ray binaries are binary star systems that are luminous in the X-ray part of the spectrum.
It began to seem likely that most of the TeV cosmic rays detected from Earth are accelerated in rapidly rotating, highly magnetized neutron stars, acting either as ordinary pulsars or as accreting pulsars in binary star systems (X-ray pulsars that accrete matter from their companion stars).
In spite of the lower likelihood of giant planet formation, just such an object has been found in the globular cluster Messier 4. This planet was detected orbiting a pulsar in the binary star system PSR B1620-26.
This is not the case for a close binary pulsar, a system of two orbiting neutron stars, one of which is a pulsar: from the pulsar, observers on Earth receive a regular series of radio pulses that can serve as a highly accurate clock, which allows precise measurements of the orbital period.
(Cf. blue stragglers) A likely scenario is a collision with a binary star system, or between two binary systems containing white dwarfs.
Since the inner part of the accretion disc orbits faster than once a second, as the hot gas ploughs into the neutron star's surface, it torques the star up to ever higher speeds.Thus it is that a neutron star in a binary star system gets to spend its retirement years as a millisecond radio pulsar.
If the images of the two components of a binary star system can be separated by telescope, it is called a visual binary.
Most of the pulsars that spin faster than once per 20 milliseconds are part of a binary star system, but about 30% have no companions whatsoever, the scientists note.
Some planets orbit one member of a binary star system, and several circumbinary planets have been discovered which orbit around both members of binary star.
In all likelihood this is a binary star system containing a low-mass normal star and a nonluminous companion.
In the case of a binary star system where one of the stars (star 1) increases its size, star 1 will reach a limiting surface.
