In a special study, an international group of scientists comprising members from the Kavli Institute for the Mathematics and Physics of the Universe or Kavli IPMU triggered the violent collisions between supernovae and its encompassing gas that is released before theoccurrence of asupernova explosion, hence releasing off an extreme brightnes.
Multiple supernovae have been identified in the last decade with extreme luminosity one – to – two – orders of magnitude bigger than for normal supernovae of known types. Such stellar explosions are known as Superluminous Supernovae or SLSNe.
Most of them have hydrogen in their spectra, while others illustrate a lack of hydrogen. The latter are known as Type 1 or hydrogen poor SLSNe 1. The SLSNe 1 can challenge the theory of stellar evolution since even normal supernovae are not still completely comprehended from first principles.
Headed by Sternberg Astronomical Institute, the scientists Elena Soronika who was also a guest investigator at Kavli IPMU and Kavli IPMU Principal Investigator Ken – IchiNomoto, a scientific associate at Sergei Blinnikov, as well as Project researcher Alexey Tolstov, the entire group, introduced a model that can explain an extensive range of identified light curves of SLSNe – 1 in a scenario that needs much less volume of energy than other proposed models.
The models illustrating the events with the lowest energy budget involve numerous ejections of bulk in presupernova stars. Mass buildup and loss of envelopes around massive stars are common features of stellar evolution. Typically, such envelopes are rather diluted, and they do not alter drastically the light released in the majority of supernovae.
In some stances, big volume of mass is expelled just a couple of years before the ultimate explosion. Then the clouds surrounding supernovae may be quite deep. The shockwaves released in collisions of supernova ejecta and those dense shells might offer the necessary power of light to create supernova much illuminating than a naked supernova without pre – ejected surrounding substance.
Such group of the models is considered to as ‘linking’ supernovae. The authors revealed that the interacting scenario is able to explain both rapid and slowly fading SLSNe 1, so the big assortment of such intriguingly bright objects can, in reality, be almost simple supernovae placed into extraordinary surroundings.
Exclusiveness is the chemical composition of the circumstellar clouds. Normally, stellar wind comprises of mostly hydrogen, as all thermonuclear reactions occur in the center of a star, while other exterior layers are hydrogenous.In the SLSNe situation, things must be different. The progenitor star must lose its hydrogen and become a big part of helium well before the release, so that a couple months to a few years before the explosion, it releases mostly oxygen and carbon, and then explode inside that dense CO cloud.
Conclusion
Only this sort of composition can explain the photometric and spectral features of identified hydrogen – poor SLSNe in the interacting scenario. It is a limitation of the stellar evolution theory to explain the origin of such helium and poor hydrogen progenitors and the highly intensive mass loss of CO before the eventual explosion.
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