A groundbreaking discovery has been made by an international team of astronomers, led by Professor Bing Zhang from the University of Hong Kong (HKU). The team has revealed the first decisive evidence that some fast radio bursts (FRBs) originate from binary stellar systems, rather than being isolated stars as previously believed. This finding, published in Science, was made possible through the use of the Five-hundred-meter Aperture Spherical Telescope (FAST) in Guizhou, China, also known as the 'China Sky Eye'.
The astronomers detected a rare signal, known as an 'RM flare', which is a sudden and dramatic change in the polarisation properties of the radio signal. This signal was observed during nearly 20 months of monitoring an active repeating FRB located about 2.5 billion light-years away. The RM flare is believed to have been caused by a coronal mass ejection (CME) from a nearby companion star, which contaminated the environment of the FRB source.
This discovery provides a definitive clue to the origin of at least some repeating FRBs, according to Professor Zhang. The evidence strongly supports a binary system containing a magnetar, a neutron star with an extremely strong magnetic field, and a star like our Sun. This finding has significant implications for our understanding of FRBs and their underlying physics.
The team's long-term monitoring of FRBs with FAST has revealed the presence of a nearby companion star orbiting the FRB source. This discovery was made possible by the persevering observations using the world's best telescopes and the tireless work of the dedicated research team. The project received support from the National Natural Science Foundation of China and other national and international grants from the collaborators.
This breakthrough in understanding the origin of FRBs opens up new avenues for research and highlights the importance of long-term monitoring of these mysterious sources. It also raises intriguing questions about the prevalence of binary systems among FRBs and the role of magnetars in their formation. The team's continued efforts in this field will undoubtedly lead to further breakthroughs and a deeper understanding of the universe.
