Supernova up close
doi:10.1038/nindia.2011.114 Published online 29 July 2011
Researchers have gained new insights into the birth and evolution of a supernova, an exploding star, in the M61 galaxy about fifty million light years away from Earth. The study will help understand the evolution of the galaxy as also the metal-rich regions between star systems.
The supernova is a Type II plateau supernova called SN2008in. The researchers have observed its explosion and evolution since its discovery using Ultraviolet Optical Telescope (UVOT) on board the Swift spacecraft of the Robotic Optical Transient Search Experiment (ROTSE-III) as also the Sampurnanand Telescope. ROTSE-III is a set of four fully robotic optical telescopes installed in Australia, USA, Namibia and Turkey, and Sampurnanand is installed in Nainital, India. They monitored SN2008in in optical, X-rays, ultraviolet and near-infrared wavelengths over a span of 416 days.
They observed three consequent phases — rising, plateau and nebular — following the explosion of SN2008in. The rising phase appeared just after the explosion initiated through 'shock-breakout' process. The plateau phase came a couple of weeks after the explosion and was signified by the presence of radioactive elements like nickel. The nebular phase was mainly powered by the radioactive decay of cobalt, a daughter element of nickel.
"Observations reveal that SN2008in is a far less energetic event than the explosions needed to form black holes. The core of the progenitor of SN2008in formed a neutron star during this explosion," says Rupak Roy, one of the researchers.
- Roy, R. et al. SN 2008in—bridging the gap between normal and faint supernovae type IIP. Astrophys. J.736, 20 (2011) | Article |