Artist rendition of a radio telescope discovering ultra-fast radio bursts that were recently discovered and the focus of this recent study. (Credit: Daniëlle Futselaar/www.artsource.nl)
A recent study published in Nature Astronomy examines the discovery of what astronomers are dubbing “ultra-fast radio bursts”, a new type of fast radio bursts (FRBs) that the team determined lasts for a mind-boggling ten millionths of a second or less. Traditionally, FRBs have been found to last only thousandths of a second, but this study builds on a 2021 study that hypothesized FRBs could possibly last for millionths of a second. This also comes after astronomers recently announced the discovery of the oldest and farthest FRB ever observed, approximately 8 billion light-years from Earth.
Artist’s impression of a fast radio burst traveling through space and reaching Earth. Credit: ESO/M. Kornmesser
Fast Radio Bursts (FRBs) were first detected in 2007 (the Lorimer Burst) and have remained one of the most mysterious astronomical phenomena ever since. These bright radio pulses generally last a few milliseconds and are never heard from again (except in the rare case of Repeating FRBs). And then you have Gravitational Waves (GW), a phenomenon predicted by General Relativity that was first detected on September 14th, 2015. Together, these two phenomena have led to a revolution in astronomy where events are detected regularly and provide fresh insight into other cosmic mysteries.
In a new study led by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav), an Australian-American team of researchers has revealed that FRBs and GWs may be connected. According to their study, which recently appeared in the journal Nature Astronomy, the team noted a potential coincidence between a binary neutron star merger and a bright non-repeating FRB. If confirmed, their results could confirm what astronomers have expected for some time – that FRBs are caused by a variety of astronomical events.
CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
Like Gravitational Waves (GWs) and Gamma-Ray Bursts (GRBs), Fast Radio Bursts (FRBs) are one of the most powerful and mysterious astronomical phenomena today. These transient events consist of bursts that put out more energy in a millisecond than the Sun does in three days. While most bursts last mere milliseconds, there have been rare cases where FRBs were found repeating. While astronomers are still unsure what causes them and opinions vary, dedicated observatories and international collaborations have dramatically increased the number of events available for study.
A leading observatory is the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a next-generation radio telescope located at the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia, Canada. Thanks to its large field of view and broad frequency coverage, this telescope is an indispensable tool for detecting FRBs (more than 1000 sources to date!) Using a new type of algorithm, the CHIME/FRB Collaboration found evidence of 25 new repeating FRBs in CHIME data that were detected between 2019 and 2021.
CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
In 2017, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) began to gather light from the Universe to address some of the biggest questions and astrophysics and cosmology. Located at the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia, this interferometric radio telescope has been a game-changer for studying Fast Radio Bursts (FRBs), which remain one of the most mysterious cosmic mysteries facing astronomers today.
In the near future, CHIME will be getting an expansion that will help it more accurately identify where FRBs are coming from. This will consist of a new radio telescope outrigger located at the SETI Institute’s Hat Creek Radio Observatory (HCRO), new outriggers near Princeton, British Columbia, and at the Green Bank Observatory in West Virginia. These will work with the main CHIME telescope to localize CHIME-detected FRBs precisely in the night sky.
The CHIME cylindrical parabolic radio telescope near Penticton, BC. Credit: CHIME/DRAO/NRC
Located in the Okanagan Valley outside of Penticton, British Columbia, there is a massive radio observatory dedicated to observing cosmic radio phenomena. It’s called the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a cylindrical parabolic radio telescope that looks like what snowboarders would call a “half-pipe.” This array is part of the Dominion Radio Astrophysical Observatory (DRAO), overseen by the National Research Council (NRC).
Originally, the observatory was meant to detect radio waves from neutral hydrogen gas in the early Universe. Today, it is used for other objectives, such as detecting and studying Fast Radio Bursts (FRBs). Since it became operational, CHIME scientists have been busy sorting through terabytes of data to pinpoint signals, often finding several in a single day. To assist with all this data-mining and coordinate CHIMEs efforts with other facilities worldwide, scientists from McGill University have developed a new system for sharing the enormous amount of data CHIME generates.
CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
Much like Dark Matter and Dark Energy, Fast Radio Burst (FRBs) are one of those crazy cosmic phenomena that continue to mystify astronomers. These incredibly bright flashes register only in the radio band of the electromagnetic spectrum, occur suddenly, and last only a few milliseconds before vanishing without a trace. As a result, observing them with a radio telescope is rather challenging and requires extremely precise timing.
Hence why the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia launched the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in 2017. Along with their partners at the National Radio Astronomy Observatory (NRAO), the Massachusetts Institute of Technology (MIT), the Perimeter Institute, and multiple universities, CHIME detected more than 500 FRBs in its first year of operation (and more than 1000 since it commenced operations)!
Artist’s impression of CSIRO’s Australian SKA Pathfinder (ASKAP) radio telescope finding a fast radio burst and determining its precise location. The KECK, VLT and Gemini South optical telescopes joined ASKAP with follow-up observations to image the host galaxy. Credit: CSIRO/Dr Andrew Howells
In September of 2017, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in British Columbia commenced operations, looking for signs of Fast Radio Bursts (FRBs) in our Universe. These rare, brief, and energetic flashes from beyond our galaxy have been a mystery ever since the first was observed a little over a decade ago. Of particular interest are the ones that have been found to repeat, which are even rarer.
Before CHIME began collecting light from the cosmos, astronomers knew of only thirty FRBs. But thanks to CHIME’s sophisticated array of antennas and parabolic mirrors (which are especially sensitive to FRBs) that number has grown to close to 700 (which includes 20 repeaters). According to a new study led by CHIME researchers, this robust number of detections allows for new insights into what causes them.
Taken with the HAWK-I instrument on ESO’s Very Large Telescope in the Chilean Atacama Desert, this stunning image shows the Milky Way’s central region with an angular resolution of 0.2 arcseconds. This means the level of detail picked up by HAWK-I is roughly equivalent to seeing a football (soccer ball) in Zurich from Munich, where ESO’s headquarters are located. The image combines observations in three different wavelength bands. The team used the broadband filters J (centred at 1250 nanometres, in blue), H (centred at 1635 nanometres, in green), and Ks (centred at 2150 nanometres, in red), to cover the near infrared region of the electromagnetic spectrum. By observing in this range of wavelengths, HAWK-I can peer through the dust, allowing it to see certain stars in the central region of our galaxy that would otherwise be hidden.
A team of scientists in Canada have found a Fast Radio Burst (FRB) that repeats every 16 days. This is in stark contrast to other FRBs, which are more sporadic. Some of those sporadic FRBs occur in clusters, and repeat irregularly, but FRBs with a regular, repeatable occurrence are rare.
CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
Canadian scientists using the CHIME (Canadian Hydrogen Intensity Mapping Experiment) have detected 13 FRBs (Fast Radio Bursts), including the second-ever repeating one. And they think they’ll find even more.
CHIME is an innovative radio telescope in the Okanagan Valley region in British Columbia, Canada. It was completed in 2017, and its mission is to act as a kind of time machine. CHIME will help astronomers understand the shape, structure, and fate of the universe by measuring the composition of dark energy.
CHIME’s unique design also makes it well-suited for detecting fast radio bursts.
The CHIME Telescope, located at the Dominion Radio Astrophysical Observatory (DRAO), in British Columbia. Credit: chime-experiment.ca
Since they were first detected in 2007, Fast Radio Bursts (FRBs) have been a source of mystery to astronomers. In radio astronomy, this phenomenon refers to transient radio pulses coming from distant sources that typically last a few milliseconds on average. Despite the detection of dozens of events since 2007, scientists are still not sure what causes them – though theories range from exploding stars, black holes, and magnetars to alien civilizations!
To shed light on this mysterious phenomena, astronomers are looking to new instruments to help search for and study FRBs. One of these is the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a revolutionary new radio telescope located at the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia. On July 25th, still in its first year, this telescope made its first-ever detection, an event known as FRB 180725A.
The detection of FRB 180725A was announced online in a “Astronomer’s Telegram” post, which is intended to alert the astronomical community about possible new finds and encourage follow-up observations. The detection of FRB 180725A is very preliminary at this point, and more research is needed before its existence as an FRB can be confirmed.
As they stated in the Astronomers Telegram announcement, the radio was signal was detected on July 25th, at precisely 17:59:43.115 UTC (09:59.43.115 PST), and at a radio frequency of 400 MHz:
“The automated pipeline triggered the recording to disk of ~20 seconds of buffered raw intensity data around the time of the FRB. The event had an approximate width of 2 ms and was found at dispersion measure 716.6 pc/cm^3 with a signal-to-noise ratio S/N ~20.6 in one beam and 19.4 in a neighboring beam. The centers of these, approximately 0.5 deg wide and circular beams, were at RA, Dec = (06:13:54.7, +67:04:00.1; J2000) and RA, Dec = (06:12:53.1, +67:03:59.1; J2000).”
Research into Fast Radio Bursts is still in its infancy, being a little more than a decade old. The first ever to be detected was the famous Lorimer Burst, which was named after it discoverer – Duncan Lorimer, from West Virginia University. This burst lasted a mere five milliseconds and appeared to be coming from a location near the Large Magellanic Cloud, billions of light years away.
So far, the only FRB that has been found to be repeating was the mysterious signal known as FRB 121102, which was detected by the Arecibo radio telescope in Puerto Rico in 2012. The nature of this FRB was first noticed by a team of students from McGill University (led by then-PhD Student Paul Scholz), who sifted through the Arecibo data and determined that the initial burst was followed by 10 additional burst consistent with the original signal.
The NSF’s Arecibo Observatory, which is located in Puerto Rico, is the world largest radio telescope. Arecibo detected 11 FRBs over the course of 2 months. Credit: NAIC
In addition to being the first time that this Canadian facility detected a possible FRB coming from space, this is the first time that an FRB has been detected below the 700 MHz range. However, as the CHIME team indicate in their announcement, other signals of equal intensity may have occurred in the past, which were simply not recognized as FRBs at the time.
“Additional FRBs have been found since FRB 180725A and some have flux at frequencies as low as 400 MHz,” they wrote. “These events have occurred during both the day and night and their arrival times are not correlated with known on-site activities or other known sources of terrestrial RFI (Radio Frequency Identification).”
As a result, this most-recent detection (if confirmed) could help astronomers shed some additional light on what causes FRBs, not to mention place some constraints on what frequencies they can occur at. Much like the study of gravitational waves, the field of study is new but rapidly growing, and made possible by the addition of cutting-edge instruments and facilities around the world.
