Washington, July 15 (ANI): NASA's Fermi Gamma-ray Space Telescope has found the core of an active galaxy, where a feeding supermassive black hole drives oppositely directed particle jets, as revealed by gamma rays.
Gamma rays from the narrow-line Seyfert 1 galaxy PMN J0948+0022 show that its central black hole drives a fast-moving particle beam.
The object lies 5.5 billion light-years away in the constellation Sextans.
Brighter colors indicate higher numbers of gamma rays at energies above 200 million electron volts. For comparison, the energy of visible light is between two and three electron volts.
NASA's Fermi Gamma-ray Space Telescope sees NGC 1275, the core member of the Perseus cluster of galaxies, as a source of high-energy gamma rays, but the earlier Compton mission did not.
The beam from this galaxy's central black hole strengthened in the years between the two missions.
Back in June 1991, just before the launch of NASA's Compton Gamma-Ray Observatory, astronomers knew of gamma rays from exactly one galaxy beyond our own.
To their surprise and delight, the satellite captured similar emissions from dozens of other galaxies.
Now its successor, the Fermi Gamma-ray Space Telescope, is filling in the picture with new finds of its own.
"Compton showed us that two classes of active galaxies emitted gamma rays - blazars and radio galaxies," said Luigi Foschini at Brera Observatory of the National Institute for Astrophysics in Merate, Italy.
"With Fermi, we've found a third - and opened a new window in the field," he added.
Using Fermi's Large Area Telescope (LAT), Foschini and his colleagues detected gamma rays from a Seyfert 1 galaxy cataloged as PMN J0948+0022, which lies 5.5 billion light-years away in the constellation Sextans.
Splitting the light from this source into its component colors shows a spectrum with narrow lines, which indicates slower gas motions and argues against the presence of particle jet.
"But, unlike ninety percent of narrow-line Seyfert 1 galaxies, PMN J0948 also produces strong and variable radio emission," said Gino Tosti, who leads the Fermi LAT science group studying active galaxies at the University and National Institute of Nuclear Physics in Perugia, Italy.
"This suggested the galaxy was indeed producing such a jet," he added.
"The gamma rays seen by Fermi's LAT seal the deal," said team member Gabriele Ghisellini, a theorist at Brera Observatory. "They confirm the existence of particle acceleration near the speed of light in these types of galaxies," he added. (ANI)