Researchers say gamma-ray bursts, or GRBs may be the byproduct of black hole formation. As a giant star collapses into a black hole, the idea goes, an extremely strong electric field can form. This energy would then be converted into matter and anti-matter electrons in a tiny fraction of a second. The opposing electrons would then collide, generating an enormous pulse of energy that races outward at nearly the speed of light.

This expanding field of energy then runs into stuff leftover when the original star collapsed, and it heats this material to billions of degrees. This heated material, in turn, expands at the speed of light and produces the burst of gamma rays.

The idea is put forth in the July 10th issue of The Astrophysical Journal Letters by a team of researchers led by Remo Ruffini of the University of Rome.

The researchers studied data on a gamma-ray burst observed in 1999, called GRB 991216, and an afterglow of X-ray emissions subsequently recorded. The data was collected by the Chandra X-ray Observatory, the Italian-Dutch Beppo-Sax satellite and the Rossi-XTE satellite.

Ruffini and his colleagues characterized the work as the first evidence for "the explosive extraction of energy from an electromagnetic black hole." They say their new model explains the timing and intensity of the gamma-ray burst as well as the extended X-ray afterglow.

"The agreement between the theory and data is excellent," Ruffini said in a prepared statement.

For the sake of simplicity, they assumed the black hole did not rotate. But another recent study shows that not only does matter swirl into these dense objects, but the black holes themselves may rotate.

Gamma-ray bursts are cosmic explosions that are observed to produce tremendous amounts of X-rays and gamma rays in a relatively short period of time. The flashes are known to be more energetic, for an instant, than anything else in the universe. All of those observed have come from the far reaches of the cosmos.

The object studied, GRB 991216, is thought to have started as a star that was 22 times more massive than our Sun. It's estimated to be 8 billion light-years away. It was first detected by the Burst and Transient Source Experiment (BATSE) aboard the Compton Gamma-Ray Observatory on December 16, 1999, and was one of the brightest GRBs found up to that time. Chandra was pointed at the source and two days later observed the afterglow of X-rays, which researchers say may have lasted several days or weeks.

The origin of Ruffini's new idea can be traced back to 1971, when at Princeton University he and a colleague, Demetrios Christosdoulous, calculated that black holes are not just energy sinks, but can also represent huge sources of energy. A few years later, the idea emerged that the creation of matter and anti-matter electrons could extract energy from a black hole.

In a separate paper also published in The Astrophysical Journal Letters, Ruffini and colleagues suggest that their expanding fireball might cause a nearby star to go supernova, a situation where a star blows itself to smithereens. This, they say, might explain why some gamma-ray bursts have been associated with supernovae.

Other explanations for this association have been put forth by other researchers. One idea is that gamma-ray bursts are sometimes just supernovae seen at a certain angle, when the bulk of their energy is directed earthward.

Click here to learn more about gamma-ray bursts and supernovae.