Identified in NGC 253, an active starburst galaxy approximately 11 million light-years away from Earth in the Sculptor constellation , the pulses from this event, named GRB 2001415, come from a magnetar, scientists at the Institute explain. of Astrophysics of Andalusia of the Higher Council for Scientific Research (IAA-CSIC) and the University of Malaga, who publish their study in the journal Nature.
Using the Atmosphere-Space Interactions Monitor (ASIM) aboard the International Space Station, astrophysicists detected two quasi-periodic pulsations at the main peak of GRB event 2001415. During the approximately 160 ms duration of the flare, around of 1046 erg of equivalent energy, approximately the energy that the Sun radiates in about 100,000 years.
“Even in an inactive state, magnetars can be a hundred thousand times more luminous than our Sun, but in the case of GRB 2001415, the energy that was released is equivalent to that radiated by our Sun in 100,000 years ”, explains Castro-Tirado .
Since its discovery, on April 15, 2020, “we have carried out very intense data analysis work, since it was a 1016 Gauss neutron star and was located in another galaxy. A true cosmic monster!” , says Víctor Reglero, astrophysicist at the University of Valencia and co-author of the work.
According to the team, the eruptions in magnetars may be due to instabilities in their magnetosphere or to a kind of “earthquakes” produced in their crust, a rigid and elastic layer about a kilometer thick.
In this case, the volume of the flare was similar to or even larger than that of the neutron star itself.
Referencia: A.J. Castro-Tirado et al. 2021. Very-high-frequency oscillations in the main peak of a magnetar giant flare. Nature 600, 621-624; doi: 10.1038/s41586-021-04101-1
