A Magnetar is a type of neutron star
with very powerful magnetic fields. They are usually produced when a heavy star
(10-25 times mass of the sun) collapse and their density is very high that one
spoon of magnetar will weigh more than 100 million tons. When the magnetars' magnetic field is
disturbed with starquakes or any such phenomenon it results in the emission of
powerful gamma-ray flares and this has been observed on earth in 1979, 1998, and
2004 (Kouveliotou et al., ManetarsArchived 2007-06-11 at the Wayback Machine,
Scientific American, 36, 2003).
When two neutron stars merge, they
collapse into a black hole in few milliseconds. Few researchers from North
Western University, United States, observed a blast of gamma rays called Short
Gamma-ray bursts on May 22, 2020, from NASA's Neil Gehrels Swift Observatory.
That light was a kilonova (which is typically brighter than 1000 times the
classical supernova) and could be produced by the birth of magnetar with the merger
of two neutron stars. It was a very strange phenomenon that was never observed
before and threw light on the new form of magnetar birth. This discovery helps to explore the diversity of kilonovae and
their remnant objects.
Reference
W. Fong (Northwestern/CIERA), T. Laskar, J. Rastinejad, A. Rouco Escorial, G. Schroeder, J. Barnes, C. D. Kilpatrick, K. Paterson, E. Berger, B. D. Metzger, Y. Dong, A. E. Nugent, R. Strausbaugh, P. K. Blanchard, A. Goyal, A. Cucchiara, G. Terreran, K. D. Alexander, T. Eftekhari, C. Fryer, B. Margalit, R. Margutti, M. Nicholl. The Broad-band Counterpart of the Short GRB 200522A at z=0.5536: A Luminous Kilonova or a Collimated Outflow with a Reverse Shock? Astrophysical Journal (accepted), 2020
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