Astronomers propose new physical interpretation of a supernovaJune 10th, 2009 - 2:18 pm ICT by ANI
Washington, June 10 (ANI): Astronomers from Queen’s University Belfast have proposed a new physical interpretation of a supernova discovered on 7th November 2008.
A group of researchers, led by Dr. Stefano Valenti from Queen’s University Belfast, found a weak explosion that is unusual in many ways, and several lines of evidence suggest it could be from a massive star.
This goes against mainstream thinking in the astrophysics community which believes that this type of supernova comes from old white dwarf stars (low-mass stars) in binary systems.
The supernova in question SN2008ha was a faint explosion that contained no hydrogen.
In their research paper however, Valenti and his colleagues propose that the peculiar spectrum and faint luminosity of the supernovae in question, SN2008ha, more closely resembles those supernovae associated with the death of massive stars when their core collapses.
The key difference with the other faint explosion of massive stars was the lack of hydrogen, which is usually detected in underluminous Supernovae.
According to Dr Valenti, “SN2008ha is the most extreme example of a group of supernovae that show similar properties. Up until now, the community had thought that they were from the explosion of white dwarfs, which we call type Ia supernovae. Those are the ones that have been used to measure the geometry of the distant Universe and infer the existence of dark energy.”
“But, we think SN2008ha doesn’t quite fit this picture and appears physically related to massive stars,” he said.
“This is still quite controversial, we have put this idea forward and it certainly needs to be taken seriouslym,” added Professor Stephen Smartt from Queen’s.
“The implications are quite important. If this is a massive star explosion, then it is the first one that might fit the theoretical models of massive stars that lose their outer layers through their huge luminosity pressure and then, perhaps, collapse to black holes with a whimper,” he said.
Dr Valenti’s team is keen to use new deep, time resolved surveys of the Universe to find more of these and test their ideas. (ANI)
Tags: binary systems, dark energy, distant universe, extreme example, luminosity, mass stars, massive star, massive stars, outer layers, physical interpretation, professor stephen, s university, smartt, star explosion, theoretical models, type ia supernovae, university belfast, valenti, white dwarf stars, white dwarfs