Friday, 24 December 2021 | PNS | Nainital
Scientists have found the first clues to understand violent short duration flares from a compact star of rare category called magnetar located thirteen million light years away. These compact stars with the most intense magnetic field known, of which only 30 have been spotted so far in our galaxy, suffer violent eruptions that are still little known due to their unexpected nature and their short duration.
A scientific group headed by professor Alberto J Castro-Tirado from the Andalusian Institute of Astrophysics (IAA-CSIC) studied an eruption in detail, managing to measure different oscillations or pulses during the instants of highest energy, which are a crucial component in understanding giant magnetar flares. Shashi Bhushan Pandey from Aryabhatta Research Institute of Observational Sciences (ARIES) in Nainital worked closely with Castro-Tirado and other group members in this research which has been published in the journal Nature. This is the first extragalactic magnetar studied in detail.
“Even in an inactive state, magnetars can be many thousands times more luminous than our sun. But in the case of the flash we have studied, GRB2001415, which occurred on April 15, 2020 and lasted only around one tenth of a second, the energy that was released is equivalent to the energy that our Sun radiates in 1,00,000 years. The observations revealed multiple pulses, with a first pulse appearing only about tens of microseconds, much faster than other extreme astrophysical transients,” said lead author Castro-Tirado.
The eruption was detected by the Atmosphere-Space Interactions Monitor (ASIM) instrument, on board the International Space Station.
“Continuous monitoring of magnetars in nearby galaxies will help to understand this phenomenon and will also pave the way to learn more about fast radio bursts, today one of the most enigmatic phenomena in astronomy”, said Pandey, one of the co-authors of the article.