July 5, 2013
Mysterious Flashes Could Be Blitzars, Dying Neutron Stars
John P. Millis, PhD for redOrbit.com - Your Universe Online
Radio observatories have recently noticed bursts of radio light emerging in the night sky. The intense flashes exist for only a moment then disappear and do not seem to repeat.
These so called 'blitzars' are a mystery, but researchers Heino Falcke (Max-Plank Institute for radio astronomy) and Luciano Rezzolla (Albert-Einstein Institute in Potsdam) have suggested we may be witnessing the death-cry of a supermassive pulsar collapsing into a black hole.
Usually, solar cores greater than about two solar masses will immediately collapse into a black hole following a supernova event. However, in extreme cases that rapid rotation of the core can cause the process to stop at the neutron star phase, persisting for perhaps millions of years.
Eventually, the neutron star will slow due to the magnetic field interacting with the interstellar medium. Once the angular momentum is no longer able to sustain the neutron star, it will collapse under its own gravity into a black hole.
During this process the intense magnetic field of the neutron star would disintegrate, casting the energy of the field into the surrounding space. (While neutron stars have incredibly powerful magnetic fields, black holes are comparatively weak.) This "casting-off" of the magnetic field energy could manifest itself as a flash of radio light.
In theory, the location of the millisecond radio burst should be coincident with a young stellar mass black hole. However, it is speculated that these objects would lie in distant galaxies, perhaps beyond our current ability to confirm their existence. However, this would provide a means to trace the rate of core-collapse supernovae throughout the Universe.
A preprint of their theory paper, submitted to Astronomy & Astrophysics, can be found here.