CSIRO's 64-m Parkes radio telescope in eastern Australia has caught "fast radio burst" for the first time, according to a joint press release from The Royal Astronomical Society in the U.K. on behalf of CAASTRO and CAASTRO The Arc Centre of Excellence for All-Sky Astrophysics. This is the first time a sharp radio flash from an unknown source has been caught live.
The first radio burst was discovered in 2007 by astronomers working on the Parkes data archive. The first burst lasted only milliseconds. Since then, there have been six more flashes that scientists believe are coming from outside our galaxy.
"These bursts were generally discovered weeks or months or even more than a decade after they happened! We're the first to catch one in real time," said Emily Petroff, a Ph.D. candidate co-supervised by CSIRO and by Swinburne University of Technology in Melbourne, Australia. Swinburne is a member institution of the ARC Centre of Excellence for All-Sky Astrophysics (CAASTRO).
The burst was only radio - no optical, infrared, ultraviolet or X-ray follow up. "That in itself rules out some possible candidates, such as long gamma-ray bursts and nearby supernovae," said team member Mansi Kasliwal from the Carnegie Institution in Pasadena, Calif.
Kasliwal said that low-energy gamma-ray bursts, imploding neutron stars and giant flares from distant magnetars ("most magnetic stars in the universe") can't be ruled out.
By identifying the characteristics of the radio signals, scientists can determine how far away the origin of the burst is. The last bust was determined to be 5.5 billion light-years away. "That means it could have given off as much energy in a few milliseconds as the Sun does in a day," said team member Daniele Malesani of the University of Copenhagen, according to the press release.
The real-time detection of the burst also left another clue - its polarization. The vibration from electromagnetic waves can be linear or circular. The radio burst caught by Petroff was more than 20 percent circularly polarized. That means there should be magnetic fields close to the source.
"We've set the trap," said Petroff. "Now we just have to wait for another burst to fall into it."
According to CAASTRO's website: "CAASTRO is a collaboration between Curtin University, The University of Western Australia, the University of Sydney, the Australian National University, the University of Melbourne, Swinburne University of Technology and the University of Queensland. It is funded under the Australian Research Council Centre of Excellence program and receives additional funding from the seven participating universities and the NSW State Government Science Leveraging Fund."
