According to foreign media reports, the mystery of the rapid radio burst (FRB) from space may be one step closer to being solved. Recently, when astronomers are studying repeated signals from nearby galaxies, they have discovered the lowest-frequency radiation of all FRBs so far, which provides new potential clues to their origin. FRBs are just as they sound-bursts of radio signals lasting only a few milliseconds.
Since they were first detected more than ten years ago, they have poured in from all corners of the sky, and each detection either deepens the mystery or brings new clues-sometimes both appear at the same time.
Some of these events are one-time, while others appear to be random or recurring on a predictable schedule. Researchers’ studies of the radio waves they emit provide additional clues to the environment in which they are generated – some signals appear to come from a calm environment, while others are distorted and polarized, indicating that they are disturbed by a strong magnetic field.
Now, in two studies, astronomers have discovered new details that may help solve this mystery. Both studies focused on a signal called FRB 180916, which was first detected in 2018 and traced back to a galaxy only 500 million light-years away. It is like a clock, repeating on a 16-day cycle, 4 of which are active, and then quiet for the next 12 days.
Astronomers examined this object in the first study by using two different radio telescopes-CHIME in Canada and LOFAR in the Netherlands. Through the latter, the research team detected 18 FRBs with frequencies between 110 and 188 MHz, which is far lower than any FRB previously observed.
Ziggy Pleunis, a lead author of the research paper, said: “We detected that FRB dropped to 110MHz, and it only existed at 300MHz before that. This tells us that the area around FRB must be transparent to low-frequency radiation, and some theories It is believed that all low-frequency radiation will be absorbed immediately and will never be detected.”
Interestingly, however, the research team also noticed a significant delay between frequencies. Three days before the lower frequency is detected by LOFAR, the higher frequency will always reach the time signal.
“At different times, we will see FRBs of different frequencies,” said Jason Hessels, the co-author of the study. “FRBs may be part of a binary star. If this is the case, we will treat these huge numbers at different times. There are different opinions on the place where the energy bursts are generated.”
In the second study, another group of astronomers tested FRB 180916 with a higher “temporal resolution” than before. As a result, they found that the polarization of the burst changes every microsecond, and they hypothesized that this might be the influence of the “dancing” magnetosphere, such as the magnetosphere surrounding a neutron star.
This adds weight to the mainstream theory about the origin of FRBs-magnetars. A magnetar is a neutron star with a very strong magnetic field. The most conclusive evidence comes from last year when scientists detected FRB-like signals from a magnetar in the Milky Way.
I believe that with the continuous increase in the research of these strange signals, the more likely it is to find clues to solve the whole mystery. The researchers said that FRB may be able to transmit at lower frequencies, but has not yet launched research on it, and future work will try to detect these frequencies.