First white dwarf pulsar to be ever discovered

Scientists have found an extraordinary binary system – a white dwarf pulsar – the first of its kind to be discovered.

The professors from the University of Warwick –  Tom Marsh  and Boris Gansicke aided by Dr David Buckley from the South African Observatory – found that the star AR Scorpii was the first white dwarf pulsar. It was first found back in the 60s.

 

This exotic dwarf pulsar has been eluding astronomers for more than five decades.

 

AR Scorpii consists of a swiftly spinning, stellar remnant –  a white dwarf, that pummels its companion red dwarf with strong rays of radiation, causing the binary system to dim and brighten every 2 minutes.

The researchers found out that the beams from this exotic star are concentrated beams of radiation, much like a particle accelerator. This is something entirely inimitable in the entire universe.

The AR Scorpio system is located in the constellation Scorpius, about 380 light-years from our planet.

The mass of the white dwarf in this system is over 200,000 times of Earth while having the same radius, and orbits a red dwarf  three times smaller than our Sun. The stars orbit at about 1,4 million kilometers from each other.

The electromagnetic field of the dwarf is truly enormous – over 100 million times stronger than Earth’s, and it spins around its axis in less than two minutes. Because of this it produces massive lasers of radiation and particles in which its companion basks.

The scientists discovered that these beams accelerated the electrons in the red dwarf atmosphere to the speed of light, a speed never reached by other binary stars.

“The new data show 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.

“AR Sco is like a gigantic dynamo: a magnet, size of the Earth, with a field that is ~10.000 stronger than any field we can produce in a laboratory, and it is rotating every two minutes. This generates an enormous electric current in the companion star, which then produces the variations in the light we detect.” – Boris Gansicke added.

Source : Sciencedaily.com