studies reveal details about origins

Fast radio waves, or FRBs, are powerful, bright emissions of radio waves ranging from a fraction of a millisecond to several thousandths of a second, each producing energy equivalent to the annual output of the Sun.

Recent research suggests that some FRBs originate from magnetars, which are neutron stars with extremely strong magnetic fields. A fast radio burst found in the Milky Way was associated with a magnetar, according to a 2020 study.

But scientists have not yet determined the origin of cosmic FRBs, which are billions of light-years away. That’s the dilemma that led an international team of scientists to see what they could learn from observing nearly 1,900 bursts from an active fast radio burst source outside our galaxy called FRB 20201124A, according to a study published Sept. 21 in Nature.

Emissions associated with FRB 20201124A occurred over 82 hours over 54 days in the spring of 2021, making it one of the most energetic fast radio bursts. It was visible through the world’s largest radio telescope – the Five Hundred Meter Aperture Spherical Radio Telescope, or FAST.

During the first 36 days, the study team was surprised to see irregular, short-lived variations in the Faraday rotation scale, which measures the strength of the magnetic field and the density of particles in the vicinity of FRB 20201124A. A larger rotation scale means the magnetic field near the radio burst source is stronger, more intense, or both, and a smaller scale means the opposite, study co-author and astrophysicist Bing Zhang said via email.

“This does not reflect the beginning (of the life) of FRBs,” said Zhang, founding director of the Center for Astrophysics at the University of Nevada, Las Vegas. “The FRB source has been there for a long time, but has been dormant most of the time. Sometimes it wakes up (this time for 54 days) and emits many explosions.”

The scales bobbed up and down during that time period, then stopped for the last 18 days before the FRB descended — “indicating that the strength and/or intensity of the magnetic field along the line of sight near the FRB source varies with time.” “This indicates that the FRB source environment is dynamically evolving, with rapidly changing magnetic fields, densities, or both.”

“It’s as if I’m filming the FRB’s source environment, and our film has revealed a complex, dynamically evolving magnetic environment never imagined before,” Zhang said in a press release.

and the physical model Another team of researchers suggested, based on observations of FRB 20201124A, that the FRB came from a binary system about 8,480 light-years away that contains a magnetar and the Be star, which is a much hotter, larger star that orbits faster than the Sun, according to a separate study published on 21 September in the journal Nature Communications.

The researchers found that the complex magnetic environment of the radio burst lies within an astronomical unit (the distance between the Earth and the Sun) of its source.

They also discovered that the explosion originated from a narrow, metal-rich spiral galaxy similar in size to the Milky Way, using the 10-meter Keck telescopes at Mauna Kea in Hawaii. The source of the radio burst is located between the spiral arms of the galaxy where no significant star formation occurs, making it unlikely that the origin was solely a magnetar, according to Nature study co-author Sobu Dong, an associate professor at the Kavli Institute for Astronomy and Astrophysics. at Peking University.

Hear the sound of space rocks crashing into Mars

“This kind of environment is not directly predictable for an isolated magnetar,” Zhang said in a press release. “Maybe there’s something else near the FRB engine, maybe it’s a binary companion.”

The authors said the modeling study should encourage further investigations of fast radio burst signals from Be star/X-ray binaries.

“These notes took us back to the drawing board,” Zhang said. “FRBs are apparently more mysterious than we imagined.” More observational campaigns with more wavelengths are needed to reveal the nature of these things.”

PREV Vivo X80 Lite 5G, a phone that changes colors, has been unveiled
NEXT Guardiola compared Haaland to Cruyff