Mysterious radio signals from deep space detected

FRB Origin

Mysterious radio signals from deep space detected

A fantastically bright repeating radio signal from billions of light-years away has been discovered, only the second of its kind ever found. Scientists now believe these signals are much more common than previously thought.

Image: The telescope detected the signals over a three week period during the summer. Fast radio bursts might actually be common - it's just that we're only just noticing them.

Of the FRBs observed to date, repeating bursts from a single source had been found only once before - a discovery made by the Arecibo radio telescope in Puerto Rico in 2015.

The highly unusual repeating signal was among 13 fast radio bursts - known as FRBs - and came from the same source, about 1.5 billion light years away.

"By understanding these propagation effects and being able to separate them from the intrinsic characteristics of FRBs, we hope to be able to use FRBs as probes of the electron distribution and magnetic field distribution in the Universe which would tell us about how the Universe built up structures, such as galaxies, galaxy clusters, and so on", explained Tendulkar.

The new FRBs were detected by the brand new CHIME instrument, or Canadian Hydrogen Intensity Mapping Experiment, located in the Okanagan Valley of British Columbia.

"Until now, there was only one known repeating FRB.", astronomer Ingrid Stairs, also a member of the CHIME team, said. Whatever they are, CHIME's initial detections suggest that the $13 million radio telescope will be a powerful tool for tracking down more of the bursts.

There are a number of theories about what could be causing them.

The CHIME researchers are working with an array of antennas in central New Mexico to pin down the galaxy to which the second repeater belongs.

CHIME scans the entire Northern Hemisphere every day, hopping from one spot to the next every 15 minutes.

First detected in 2002, fast radio bursts (FRBs) continue to mystify astronomers, who have struggled to understand the sources of these powerful emissions.

The CHIME/FRB Collaboration includes scientists from UBC and McGill as well as the University of Toronto, the Perimeter Institute for Theoretical Physics and the National Research Council of Canada.

While most FRBs have been spotted at wavelengths of a few centimetres, the latest FRBs were detected at wavelengths of almost a metre, which opens up new lines of inquiry, according to the CHIME team. 400 Mhz is the lower limit of the CHIME experiment at the moment, so other FRBs at lower frequencies could simply be going undetected.

Before CHIME began to gather data, some scientists wondered if the range of radio frequencies the telescope had been created to detect would be too low to pick up fast radio bursts.

A majority of the intercepted fast radio bursts shows signs of "scattering", a phenomenon that reveals information about the environment where the radio waves originated from, Phys.org reported.

Added Landecker: "We haven't solved the problem, but it's several more pieces in the puzzle".

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