Astro-boffins plan 3D plot of the universe

Only a few of them have been observed so far, but boffins from the University of British Columbia reckon fast radio bursts (FRBs) could help refine our understanding of where stuff is in the universe.

Their work, published in Physical Review Letters and announced here, proposes that the way FRBs spread across different wavelengths and in time as they arrive to Earth could help better map the universe in three dimensions.

As the university explains, this “spreading” takes place because the FRBs pass through a lot of matter before we see them, interacting with electrons on the way.

“The amount of spread in the signal that arrives on Earth gives scientists a sense of how many electrons, and by extension how much material including stars, gas and dark matter, are in between Earth and the source of the burst”, the release says.

And that means the time differences of different wavelengths from a single FRB source could help pin down the location of the intervening mass.

The first step to testing that will be to identify as many FRBs as possible, and that's no easy task.

The very first FRB was only discovered in 2013 in archival data collected by Australia's Parkes radio-telescope, and it wasn't until January of this year that Swinburne University PhD student Emily Petroff first observed an FRB in real time.

In verifying the discovery, Petroff had to demonstrate that the FRB she had caught really was of extra-terrestrial origin, and not (as some signals were) coming from a microwave oven.

Although they're hard to observe, astro-boffins believe Earth could see thousands of FRBs each day if we search for them the right way.

The UBC scientists want to press the Canadian Hydrogen Intensity Mapping Experiment (CHIME) for this. CHIME, currently under construction in Penticton in Canada, is a curious static design based on cylindrical reflectors whose field of view sweeps as the Earth turns.

The size of the instrument means it has enough resolution to map what its operators call “baryon acoustic oscillations” imprinted on cosmic structure.

According to project member, UBC associate professor Kris Sigurdson, the instrument “has the potential of seeing tens to hundreds of these events per day so we can build a catalogue of events. If they are cosmological, we can use this information to build a catalogue of galaxies.” ®