Until that time, all Feds had been observed outside our galaxy. Pragya Chawla, a PhD candidate in physics at McGill University in Canada, said: It was also worth noting that the April 2020 discovery was the most energetic radio explosion ever recorded by astronomers in the River of Heaven, but the most exciting is since it was first discovered by scientists. It is closer to identifying the origin of the FRB than at any point in time. ..
It happened in 2007 when Duncan Lorimar and David Narkevic were studying data taken on a radio dish in Parks, Australia. Discovering the Fed near home is a breakthrough that astronomers have been hoping for ever since. “We can learn more from light sources that are 30,000 light-years away than those that are more than a billion light-years away,” Masui asserts. “We finally have a nearby source of information to study.”
One of the big problems with Fed detection is that it’s very fleeting, except that most of the Feds are far apart. Even though they are 100 million times more powerful than the Sun, they disappeared in a blink of an eye — in 100 years they can emit as much energy in thousands of seconds of the Sun. Ideally, astronomers discover objects and focus on one or more different telescopes, but the temporary nature of these bursts eliminates such opportunities.
However, despite these challenges, astronomers have succeeded in building a bank of knowledge about the Fed. Most of them are based on dozens of events recorded across our own galaxy. For starters, we know that it is a bright flash of wireless light that lasts from microseconds to milliseconds. “Their all-sky searches also suggest that thousands of these bursts occur in the sky every day,” Chaula added.
Impressions of the artist of the exploding SGR 1935 + 2154 magnetar. It emphasizes its complex magnetic field structure and beam emission. (Image credit: © McGill University Graphic Design Team) We also know that most of them come from billions of light-years away. However, dozens of models have been proposed to explain the origin of the Fed, but there are precursors from neutron stars to white dwarfs to cosmic strings. Is there a theory that is actually widespread? “Well, we know they come from very small sources-the size is less than a few hundred kilometers,” Masui said. “And the most likely source of information is Neutron star Because it’s very small and energetic. “
Discovered in the Milky Way, the Fed is now helping astronomers consolidate such theories, which is a breakthrough for scientists trying to reach the roots of what is causing them.
Observational evidence is now very likely that the Fed’s origin is magnetar, thanks to the work of some nifty space detectives, including data from other telescopes monitoring the same sky patch. Suggests. Magnetic fields are 5,000 trillion times stronger than Earth, thereby making them the most powerful magnets in the universe.
When it reaches the earth, the impression of an artist of high-speed radio bursts with various radio wavelengths (red is long, blue is short). (Image credit: © Jingchuan Yu, Beijing Planetarium) But how did this conclusion come about? To explain, we must consider the work that led to the study of the Fed, especially in relation to magnetars, which are known to emit high-energy electromagnetic radiation. Gamma rays X-ray .. It is speculated that both of these may erupt with short-lived flares and emit radio waves in processes that identify the magnetar as the source of the Fed.
When this latest Fed was discovered in our galaxy — known by astronomers as the Fed 200428 — it turned out to be derived from the constellation Vulpecula. It was also accompanied by a burst of X-rays that made astronomers even more excited.
The first detection of X-rays from that empty area was made the day before CHIME and STARE2 discovered FRB200428. Neil Gerelswift Observatory And that Fermi Gamma-ray Space Telescope We have detected multiple X-ray and gamma-ray bursts from SGR1935 + 2154, which are known to exhibit transient radio pulsations.
It was found that other telescopes also observed X-ray bursts from SGR 1935 + 2154 — decisively at the same time as the fast radio bursts. These included the Konus-Wind detector onboard NASA’s GGS-Wind spacecraft and the European Space Agency’s INTEGRAL space telescope, which detected X-ray bursts the moment CHIME and STARE2 recorded FRBs. ..
How to use CHIME to detect fast radio bursts A Canadian hydrogen intensity mapping experiment in Okanagan Falls was featured in FRB200428.
As another check, I focused on the 500-meter spherical radio telescope (FAST) in southwestern China. This fixed-diameter dish telescope detected a fast radio burst in the direction of FRB 200428 and placed it near SGR 1935 + 2154. This further strengthened the relationship between X-ray sources and fast radio bursts. The latter was comparable to other Feds found outside the Milky Way and was added to the body of evidence.
“This means that the FRB came from the direction of a known magnetar in our galaxy, and the radio bursts happened exactly at the same time as the X-ray bursts coming from the same magnetar,” Masui said. “It’s a clue about how magnetars generate the Fed, but the community is trying to figure out what that means.”
It became clear that the Fed 200428 was the first observed fast radio burst to transmit non-radio radiation, and scientists have greatly benefited from discovering the Fed very close to their home. .. The detection of X-ray bursts at the same time as the radio bursts confirmed the origin of the magnetar. This is the evidence that astronomers were looking for.
“It’s important that the Fed was discovered near our galaxy, because it’s so close that it’s much easier to track the light source with telescopes observing at other wavelengths,” Chaula said. Mr. says. “None of the Feds discovered so far are known to emit at other wavelengths. This is the first detection of the Fed at different wavelengths. These observations provide a more detailed look at the source environment. Investigate and provide clues about the origin of the Fed.
In particular, CHIME has proven to be an indispensable tool. Based in the Dominion Radio Astrophysical Observatory in Canada, this new radio telescope with no moving parts has a high mapping speed thanks to a 200 square degree field of view and a wide frequency range from 400MHz to 800MHz.
“Most radio telescopes cannot locate the Fed and associate it with known objects. Radio telescopes that can pinpoint the Fed very accurately usually look at small patches in the sky and only about patches. Not observable. The size of the full moon. They cannot monitor several known magneters at once, “Chaura said.
“But CHIME observes about 500 times the area, so we can monitor all magnetars in the northern sky every day, so we can detect such rare bursts. Combining localization capabilities with a large empty area. This allowed us to detect this burst and associate it with a known object. “
It was revolutionary and soon became the Fed’s main observer. The correlator supercomputer processes 13 terabits of raw data per second to create an empty radio map. “Our ability to detect the Fed in the distance has improved dramatically over the last few years,” said Masui. “Approximately 50 Feds were detected between 2007 and 2017. In the last two years, CHIME has detected hundreds. This is possible with CHIME’s digital drive design and uses digital signal processing. Then you can focus the light and see the big band. Immediately empty. “
However, the case is not completely closed by this mystery.
DIY approach to space discovery STARE2’s three wireless detectors are cobbled by students using household items.
As Chaura tells us, young extragalactic magnetars form only one of the Fed’s proposed models. Bursts from known magnetars in our own galaxy have never been observed to be as strong as those outside the galaxy, and for the purposes of Fed 200428 research, astronomers have previously observed bursts detected. I estimated it to be 3,000 times brighter than the burst. Makes the Fed’s magnetar model more plausible.
“The bursts we saw are still less energetic than most extragalactic Feds, so it’s unclear if magnetars can explain all the Feds,” Chaula said of the equivalent energy found outside the Milky Way. I mentioned a 1/1000 burst of.
Weak bursts are more common and can be a problem close enough to detect. But when it comes to fixing the Fed’s source to magnetar, astronomers need to keep in mind that it comes in two forms. It means that the signal is repeated. That is, it produces frequent bursts, such as the Fed 200428. It is generated less frequently.
Rare Feds can be caused by magnetars, and frequent Feds can be caused by other phenomena. Conversely, there are two types of magnetars, two types of fast radio bursts, and the brightest Fed can be generated by an object other than the magnetar. All we can really say for sure is that at least part of the Fed comes from magnetar, so only further research will shed light on the answer.
“It has long been suspected that magnetars may be the source of the Fed, but since we’ve confirmed that it has happened once, we’ve confirmed it with at least some magnetars,” Masui said. Said. “But I still don’t know how magnetars create them. I know” what “and next is” how “. How does a magnetar do that? “
Diagram of fast radio bursts appearing randomly across the sky. (Image credit: © Caltech; NRAO) Therefore, it remains important for the Fed to discover the power to release such energy. Perhaps the electrons interact with the magnetic field to create some sort of “engine.” “We will be interested in determining how extreme the properties of these magnetars need to be so that bursts from these magnetars can be seen throughout the universe,” Chaula said. Said. “But the most interesting use of the Fed is to use it as a cosmological probe to study the distribution of electrons and magnetic fields in the universe in unprecedented detail.”
Astronomers also continue to see how X-ray radiation and bursts of these bright energies can occur at the same time. “Whether all Feds are created by the same mechanism is an open question and has been the subject of much debate among astronomers,” says Masui. With that in mind, it’s clear that astronomers have been digging into the ongoing mysteries of fast radio bursts for some time.
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