Collisions between massive black holes may leave behind infrared afterglows

London, March 5 : A new study has suggested that powerful collisions between supermassive black holes could leave behind long-lasting infrared afterglows, which might be visible to current instruments.

A report in New Scientist states that Jeremy Schnittman and Julian Krolik from Johns Hopkins University in Maryland, US, conducted the study.

According to the study, supermassive black holes weigh millions or billions of times the mass of the Sun and appear to reside in the hearts of most galaxies the size of the Milky Way or larger.

Their mergers are predicted to be among the most powerful events in the universe, with each union generating more energy than all the stars in the cosmos combined.

Most of that energy is thought to be released in the form of gravitational waves - elusive ripples in the fabric of space that have yet to be directly detected.

But new calculations by Schnittman and Krolik have suggested that recently merged black holes give off an infrared glow for up to 100,000 years.

The persistent auras originate from the thick clouds of gas and dust, called accretion discs, which surround and sustain the black holes, the report said.

According to the calculations, when two black holes collide, the orbits of material in the disks become disturbed, causing particles to crash into one another.

"It takes a while for the gas to settle down into a new circular orbit, and as it sloshes around, it loses a lot of energy by smashing into itself," Schnittman told New Scientist.

Some of that energy is transformed into X-rays and other forms of light, which bounce around in a labyrinth of gas and dust particles in the accretion discs before ultimately escaping in the form of infrared light.

Schnittman and Krolik have also estimated that almost 100,000 infrared sources from merged supermassive black holes could be visible in the universe today.

According to researchers, the resulting infrared glow from some of these events could be visible to NASA's infrared Spitzer Space Telescope.

Also, a proposed space mission called LISA (Laser Interferometer Space Antenna) should be able to see them, but it is not expected to launch until 2018.

ANI