Tiny flame sheds new light on supernova explosions
Washington: A team of researchers has gained new insights into the titanic forces that drive Type Ia supernova explosions after studying the behaviour of small flames in the laboratory.
These stellar explosions are important tools for studying the evolution of the universe, so a better understanding of how they behave would help answer some of the fundamental questions in astronomy.
To better understand the complex conditions driving this type of supernova, the researchers performed new 3-D calculations of the turbulence that is thought to push a slow-burning flame past its limits, causing a rapid detonation - the so-called deflagration-to-detonation transition (DDT).
How this transition might occur is hotly debated, and these calculations provide insights into what is happening at the moment when the white dwarf star makes this spectacular transition to supernova.
“Turbulence properties inferred from these simulations provides insight into the DDT process, if it occurs,” said Aaron Jackson, who was a graduate student at
Stony Brook University on Long Island, New York at the time of this research.
He is currently an NRC Research Associate working in the Laboratory for Computational Physics and Fluid Dynamics at the Naval Research Laboratory in Washington, D.C.
While the deflagration-detonation transition mechanism is still not well understood, a prevailing hypothesis in the astrophysics community is that if turbulence is intense enough, DDT will occur.
Extreme turbulent intensities inferred in the white dwarf from the researchers’ simulations suggest DDT is likely, but the lack of knowledge about the process allows a large range of outcomes from the explosion.
Matching simulations to observed supernovae could identify likely conditions for DDT.
“Our goal is to provide a more realistic simulation of how a given supernova scenario will perform, but that is a long-term goal and involves many different improvements that are still in progress,” said Dean Townsley from the University of Alabama at Tuscaloosa.
The findings were presented at the American Physical Society’s (APS) Division of Fluid Dynamics (DFD) meeting in Baltimore.