WR stars are massive stars and strip their outer hydrogen envelope, which is associated with the fusion of Helium and other elements in the massive core. Tracking of certain types of massive luminous supernova explosion can help probe these stars that remain an enigma for scientists from across the world.
The four Indian scientists from the Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, an autonomous institute under the Department of Science & Technology, and 16 scientists from different institutes in the US, UK, Canada, Ireland, Italy, Sweden and Korea have conducted the optical monitoring of one such stripped-envelope supernova called SN 2015dj hosted in the Galaxy NGC 7371. They calculated the mass of the star that collapsed to form the supernovae as well as the geometry of its ejection. The scientists also found that the original star was a combination of two stars – one of them is a massive WR star and another is a star much less in mass than the Sun.
from South Korea, Mridweeka Singh, who was part of ARIES when the supernova discovery was made, said, “This supernova was discovered in 2015. We observed the supernova for up to 170 days since its discovery. Thereafter, we submitted the manuscript in February last year and it got accepted on January 22 this year. Now the paper is available online and is being published.”
Mridweeka, who moved to South Korea in 2019 after leaving the institute and is currently working for Korea Astronomy and Space Science Institute, told
, “SN 2015dj is a type Ib supernova whose progenitor was in a binary system with mass between 13 to 20 M_sun. The explosion geometry was symmetric for this supernova.” The team’s discovery and detailed study was recently published in ‘The Astrophysical Journal’.
Supernovae (SNe) are highly energetic explosions in the universe releasing an enormous amount of energy. Long-term monitoring of these transients opens the door to understand the nature of the exploding star as well as the explosion properties. It can also help enumerate the number of massive stars.
Long-term monitoring of these transients opens the door to understand the nature of the exploding star as well as the explosion properties. It can also help enumerate the number of massive stars.