Gigantic black hole involved in stellar destruction
Washington, January 5 (ANI): New results from NASA's Chandra X-ray Observatory and the Magellan telescopes have suggested that a black hole, which is a thousand times as massive as the Sun, ripped apart a dense stellar remnant.
If confirmed, this discovery would be a cosmic double play, as it would be strong evidence for an intermediate mass black hole, which has been a hotly debated topic, and would mark the first time such a black hole has been caught tearing a star apart.
This scenario is based on Chandra observations, which revealed an unusually luminous source of X-rays in a dense cluster of old stars, and optical observations that showed a peculiar mix of elements associated with the X-ray emission.
Taken together, a case can be made that the X-ray emission is produced by debris from a disrupted white dwarf star that is heated as it falls towards a massive black hole.
Irwin and his colleagues obtained optical spectra of the object using the Magellan I and II telescopes in Las Campanas, Chile.
These data reveal emission from gas rich in oxygen and nitrogen but no hydrogen, a rare set of signals from globular clusters.
The physical conditions deduced from the spectra suggest that the gas is orbiting a black hole of at least 1,000 solar masses.
The abundant amount of oxygen and absence of hydrogen indicate that the destroyed star was a white dwarf, the end phase of a solar-type star that has burned its hydrogen leaving a high concentration of oxygen.
The nitrogen seen in the optical spectrum remains an enigma.
"We think these unusual signatures can be explained by a white dwarf that strayed too close to a black hole and was torn apart by the extreme tidal forces," said coauthor Joel Bregman of the University of Michigan.
Theoretical work suggests that the tidal disruption-induced X-ray emission could stay bright for more than a century, but it should fade with time. (ANI)