It looked like a dot, but something made the experts suspicious. Who in the end were right to insist. Because they found, scanning the sky, between intuitions and verifications, the brightest extragalactic pulsar ever discovered. It is distant, in the Large Magellanic Cloud, about 160,000 light years from Earth. It was discovered by an international team of astrophysicists, among them the Italian Alessandro Ridolfi , from the National Institute of Astrophysics (INAF) of Cagliari .
The pulsar had already attracted the attention of the University of Sydney. To determine if it was really a neutron star, however, needed a radio telescope more sensitive than the Australian one and an "astronomer fact-checker", an expert able to analyze the data collected and issue the verdict. The ultra-advanced instrument was in South Africa, the MeerKat radio telescope of the South African Radio Astronomy Observatory: 64 antennas collected data for two and a half hours. But a verification was needed. And this task was entrusted to the young INAF researcher from Cagliari, but originally from Rome, Alessandro Ridolfi.
"After all - he explained to the journal of the National Institute of Astrophysics - it was a rather simple job: to use the codes that I normally use to analyze the data of the globular clusters collected with MeerKat and apply them to the new data set for Check for pulsations. Pulsations that actually existed: a relatively slow pulsar, a typical feature of the so-called 'young' pulsars, although further measurements will be needed to determine its age, so that the variation in the period of time can be calculated. rotation over time ".
"It was an incredible surprise . I didn't expect to find a new pulsar, let alone the brightest one! But with the new telescopes we now have access to, like Askap and its 'sunglasses', it's finally possible," comments the astronomer Yuanming Wang, PhD student at the University of Sydney and first author of a study - published in The Astrophysical Journal - reporting the discovery.
(Unioneonline / vl)
