Researchers for the first time has discovered a phenomena know as ‘glitch,’ timing irregularity in a binary pulsar.
When a star runs out of fuel, it collapses, and lead to a massive stellar explosion which is known as Supernova. A supernova ejects matter from the dead star in every direction while leaving a very dense chunk of object behind. Based on the size of dead star the leftover chunk can be a white dwarf, a neutron star or a black hole.
If there is a neutron star that’s left, it will most probably have a strong magnetic field and fast rotation rate. They also emit a bright beam of light that we can observe from here, when it is directed towards the Earth. It works just like a lighthouse, signaling light while rotating, but in this case its much-much massive.
The discovery was made by a group of researchers from Baskent and Middle East Technical University (METU) situated in Turkey, who identified a sudden increase in the rotational speed of the pulsar SXP 1062. These types of sudden increase is known ‘glitches’. Glitches are more commonly found in isolated pulsars, but none of the known binary pulsars (orbiting with a companion) have shown any signs of a glitch.
The SXP 1062 pulsar is located in the Small Magellanic Cloud, a very small satellite galaxy of the Milky way galaxy, which is also our nearest galactic neighbors at a distance of 200,000 light years. ‘This particular pulsar is intriguing, not only it’s locked in a binary system, revolving around a companion, it is in a close proximity to the stellar remains, which were created by a supernova explosion,’ said M. Mirac Serim, a doctoral student at METU.
Journal Reference: Discovery of a glitch in the accretion-powered pulsar
It is believed that the pulsar is sucking whatever it’s left from the explosion, this process of feeding is known as accretion. Researchers believe that the glitch of this magnitude is caused due to accretion of the stellar remnant by the pulsar and the gravitational effect of its partner star, which were exerting more and more pressure on the pulsar’s crust. When the crust couldn’t take any more pressure, it went through some rapid structural changes which caused changes in crust’s momentum, increasing the rotation speed all of a sudden. This caused the glitch.
X-ray pulsar SXP 1062 surrounded by the supernova remnant
‘The increased fractional frequency during the glitch is highest ever, which is distinctive to this very pulsar,’ said Dr. Seyda Sahiner, co-author of the paper. ‘The glitch size demonstrate that the isolated neutron stars’ interiors might not be same as the interiors of neutron stars present in binary systems’, he added.
After the analysis of pulsar SXP 1062, with the help of three space satellites, the team obtained a consistent time solution, which indicated that SXP 1062 pulsar has been steady with a spinning rate of −4.29(7)× 10¯14 Hz s¯¹ and surface magnetic field of about 1.5×10¯14 G. On 56834.5 modified Julian date (MJD), a sudden hype in pulse frequency Δν=1.28(5)×106 Hz caused the glitch.