AR Scorpii - The first discovered white dwarf pulsar (See pic)

New Delhi: An elusive white dwarf pulsar - the first of its kind ever to be discovered in the universe - housed in an exotic binary star system 380 light years away from Earth has been discovered by a team of astronomers.

The discovery was made by professors Tom Marsh and Boris Gänsicke of the University of Warwick's Astrophysics Group and Dr David Buckley of the South African Astronomical Observatory.

They identified the mysterious star dubbed 'AR Scorpii' (AR Sco) as the first white dwarf version of a pulsar - objects found in the 1960s and associated with very different objects called neutron stars.

"The new data shows that AR Sco's light is highly polarised, showing that the magnetic field controls the emission of the entire system, and a dead-ringer for similar behaviour seen from the more traditional neutron star pulsars," said Tom Marsh from University of Warwick in England.

 

The white dwarf pulsar has eluded astronomers for over half a century.

AR Sco contains a rapidly spinning, burnt-out stellar remnant called a white dwarf, which lashes its neighbour - a red dwarf - with powerful beams of electrical particles and radiation, causing the entire system to brighten and fade dramatically twice every two minutes.

The latest research establishes that the lash of energy from AR Sco is a focused 'beam', emitting concentrated radiation in a single direction much like a particle accelerator -- something which is totally unique in the known universe.

AR Sco lies in the constellation Scorpius, 380 light years from Earth, a close neighbour in astronomical terms.

The white dwarf in AR Sco is the size of Earth but 200,000 times more massive, and is in a 3.6 hour orbit with a cool star one-third the mass of the Sun, the study said.

The distance between the two stars is around 1.4 million kilometres - which is three times the distance between the Moon and the Earth.

The research titled 'Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii' has been published in the journal Nature Astronomy. 

(With IANS inputs)