Scientists like all kinds of puzzles. Astronomers love to search for them. And journalists love when explaining some phenomenon can not just astronomers – because they are the objects of research on other planets, stars and other galaxies, and there is a great temptation to attribute unexplained phenomenon actions extraterrestrial intelligent forces. So it comes with a very interesting phenomenon that is on the minds of astrophysicists last eight years – the so-called fast radio bursts (Fast Radio Bursts – FRB), which is devoted to an article in the latest issue of the journal Nature .
Despite the fact that by radio astronomers involved since the mid XX century, the first such signal was detected at all recently, in 2007. This was made possible when the astronomers learned to identify individual short bursts length of about one millisecond, and to do it was not easy, because in the radio space is always something roars.
The first spike recorded in 2007, was not similar to any previous signals, he did not come out of the plane of the galaxy, and with directions on Magellanic Cloud. In the same year, employees of the State Astronomical Institute of the Sternberg State University Sergei Popov and Konstantin Postnov published an article , which offered an explanation mysterious surge.
They proposed a mechanism that shows how these bursts can be produced on magnetars – magnetized neutron stars, the first of which was opened by the Soviet astrophysicist Eugene Mazets c coauthors.
«The situation was similar to the gamma-ray bursts open in 1960: something in the sky Bach, and we do not see where it happened, “- said” Gazeta.ru “DF-mathematical sciences Sergey Popov.
After the first burst of silence, and a second surge was caught only in 2012 in the galactic plane in 2013, were presented certificates of another four bursts.
In the same years, astronomers began to celebrate special vspleski- “peritonitis”, about which it was clear that they have a near-Earth origin, and only in 2015 was proved,
that their cause was the microwave working near the Australian Parkes telescope.
That’s when it became clear that the true FRB born in outer space. In 2014, two Australian researcher, unravel the secret of peritonitis, recorded first FRB during the actual observations – before all caught bursts were not detected during the observations, and archival data.
This is the first time allowed to bring the desired region of the sky other telescopes, optical and X-ray, however, astronomers saw nothing.
«I remember that jokes about gamma-ray bursts were limited to the fact that the number of explaining their hypotheses It exceeded the number of bursts themselves. Today radio outbursts situation is the same, “- says Popov, counted about 20 different models that describe the appearance of bursts.
Among them are cosmic strings, merging neutron stars or white dwarfs, the collapse of a neutron star into a black hole, falling asteroids on a neutron star and others.
Interest in the FRB high weekly scientists publish one or two articles on the subject.
At the end of November 2015 a group of Australian scientists an article on the new archival bursts, among which was first obtained by the double FRB.
«Dual surge explicitly covers some models that predict single splash and two – hard, “- said the scientist. The lack of response of the radio bursts at other wavelengths as is consistent with the model proposed by Russian scientists in 2007. “This is exactly what we predicted, not all models predict that other bands will be empty,” – said Popov, a regular contributor to “Gazety.Ru” going to tell in detail about the history of the opening of FRB in its public Chapter 6 December .
In an article published in the latest issue of Nature, researchers led by Kiyoshi Masui of the University of British Columbia (Canada) concluded that, whatever the source of the mysterious bursts around should be a lot of substance, through which pass the signals.
On This is indicated by a so-called Faraday rotation of the received signal from a single burst FRB 110,523 – has long been familiar to physicists effect saying that the wave passed through a magnetized medium. “This greatly reduces the restrictions on the conditions around the source and type of events that leads to a surge means that the source of the momentum is likely to lie within a region of star formation and supernova remnants,” – says Masui. According to him, magnitarnaya hypothesis, first proposed by Russian scientists (which, however, the authors do not cite) is preferred over those associated with the merger of neutron stars, and others, because such mergers occur in areas with lower density of matter in galaxies .
«source lies in some supernova remnant or in star-forming region where a lot of gas. Both are suited to the chic version of magnetars. Because magnetars have an age of a few tens of thousands of years, and we see them in the areas where active is star formation “- agrees Popov.
The detailed mechanism of the flash magnetar invented Israeli counterpart Russian astronomer Yuri Lyubarskii.
He suggested that this magnetar must be surrounded by a nebula. Then the magnetic pulse from the flash magnetars hits the nebula and is already there with the help of the laser mechanism is produced by radio waves.
Estimates show that these flares on magnetars may occur once in several hundred years, which is quite consistent with the observed statistics. “Statistics on the number of bursts in the sky that give observers give as much as give a prediction. And even if they give a splash once in your life, this corresponds to the statistics. In fact, we see synchrotron maser, it – unique thing that can be done in a vacuum, but only in a plasma, “- said Professor of Physics Faculty DF-PhD, Konstantin Postnov.
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