Researchers studied a strange fluctuation within an unexpectedly long gamma-ray burst, similar to a heartbeat. This occurred as a result of the merger of two neutron stars and the formation of a millisecond magnetar. It is also a very rare type of neutron star.
Gamma-ray bursts
Gamma-ray bursts are among the most powerful phenomena known to humans. They are virtually invisible in the visible part of the spectrum. However, they are clearly visible in the highest frequency parts of the electromagnetic spectrum. Scientists are still debating what objects generate them. But now they will be able to learn more about this.
This refers to research conducted by scientists from the University of Hong Kong and Nanjing University, as well as the Institute for High Energy Physics of the Canadian Academy of Sciences. It began with the gamma-ray burst GRB 230307A, recorded on March 7, 2023. Usually such events last about 2 seconds, but this one lasted a minute and there was a noticeable fluctuation inside it.
Researchers suspected that this could be a sign that the newborn object is also a rapidly rotating neutron star. To verify this, they organized observations using Chinese GECAM (B and C) instruments and NASA’s Fermi satellite (GBM). With their help, additional research was conducted.
What did the study show?
In total, researchers had to process more than 600 data packages. However, it was worth it. This made it necessary to prove that it was indeed a merger of two neutron stars. The gamma-ray burst theory confirms that these have to be just such objects or simply a pair of massive stars.
However, scientists were uncertain about what was formed as a result of mergers that generated gamma-ray bursts. Were they black holes or something else? A new study has shown that the burst is accompanied by something similar to a heartbeat — pulsations with a frequency of 909 Hz. They were the ones who suggested what object had been formed as a result of the incident.
It was a millisecond magnetar — a rare type of neutron star that has an extremely powerful magnetic field and rotates many times per second. Scientists now know that gamma-ray bursts are not only caused by black holes.
According to phys.org
