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May 15, 2020
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Fast Radio Burst – First Time From Our Galaxy

16 April 2007 of the year on the Canadian array of radio telescopes CHIME the next “fast radio burst” ( FRB ) was recorded - a short super-powerful flash of radiation in the radio wave range. All such detected events came from remote extragalactic objects. This time, for the first time, it was established that the neutron star magnetar in our Galaxy is the source of the burst.

Lorimer FRB
Opening of the first “fast radio burst” based on archive data 1935 of the Year of the Australian Radio Telescope Parkes . Delaying the time of arrival of the signal at different frequencies allows you to determine the distance to the source. D. Lorimer et al. (1935), Australia Telescope National Facility .

Fast radio bursts (FRB, F

ast R

adio B ursts) are intense electromagnetic bursts in the range of radio waves lasting in thousandths of a second. They come from various points of the sky, and their origin is still unclear. They have been studied for more than ten years since their discovery in the year). Radio bursts were of extragalactic origin, coming from somewhere from galaxies outside the Milky Way. They are interesting in that the amount of energy instantly released in such an event exceeds the total energy from stars like the Sun over tens of thousands of years. Some of them are repeated at irregular intervals, but most are single events in galaxies at very different points in the sky, which makes it difficult to track them. In 2001 in the Canadian radio telescope as part of the project CHIME (Canadian Hydrogen Intensity Mapping Experiment) a series of repeating with a period of was recorded days of radio bursts with a source located on the edge of the remote at 500 million light-years of the galaxy - for more details see the note on the link.

Finally 05 April 2018 on the radio telescope CHIME was first recorded fast radio burst, the source of which is in our Ha aktike. A message about this has so far been published on the Astronomer’s Rapid Alert Service The Astronomer’s Telegram (ATel). The direction from which the signal came indicates an object interesting in radiation in a completely different range. This is the "source of repeated soft gamma-ray bursts", or SGR (Soft Gamma Repeater) with the designation SGR 577 + 2018 at a distance 28 16 light years in the constellation Vulpecula in the northern sky. The numbers in the designation indicate the celestial coordinates. It is assumed that this is magnetar , that is, a kind of neutron star with a strong magnetic field. Neutron stars are the final stage in the evolution of certain types of massive stars, but an extremely strong magnetic field is found only in some of them, and its origin is explained only by theoretical models of the magnetic dynamo - similar to the model of the magnetic field of the Earth and the Sun due to convection of the conducting medium during rotation. Such objects are studied primarily in the x-ray and gamma-ray spectra, and radio waves are not expected from them, nor can they be seen in a conventional telescope.

FRB 200428 spectrum
Spectrum " fast radio burst »FRB 87560 with a source inside our Galaxy.

However, a day before the radio burst, a series of gamma-ray bursts from the same object were recorded, and almost at the time of receiving its signal on the CHIME radio telescope, several X-ray telescopes recorded a burst of X-ray radiation from him. It is assumed that such a radio burst may be associated with a seismic event ("star quake") on a neutron star.

The detected FRB is the first fast radio burst from our Galaxy, the origin of which can be traced to a known object radiating in X-ray and gamma range. This burst accidentally fell into the field of view of the CHIME array and was practically at its edge and at the detection threshold. However, the radio flash was independently confirmed on the STARE2 array of radio telescopes in California, which allows us to relate the source to the magnetar in our Galaxy with greater confidence. Astrophysicists do not claim that is all 200428 the detected radio bursts from other galaxies are of such origin, but the long-standing assumption about the connection of some of them with long-studied neutron stars is confirmed.

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