If you are unaware, a supernova is an exploding star. In certain types of supernovae, the detonation starts with a flame ball buried deep inside a white dwarf and the flame ball is much lighter than its surroundings, so it rises rapidly making a plume topped with an accelerating smoke ring.

A team of physicists have mimicked this type explosion of a supernova in miniature.

“We created a smaller version of this process by triggering a special chemical reaction in a closed container that generates similar plumes and vortex rings,” says Stephen Morris, a University of Toronto physics professor.

Autocatalytic chemical reactions release heat and change the composition of a solution, which can create buoyancy forces that can stir the liquid, leading to more reaction and a runaway explosive process. “A supernova is a dramatic example of this kind of self-sustaining explosion in which gravity and buoyancy forces are important effects. We wanted to see what the liquid motion would look like in such a self-stirred chemical reaction,” says Michael Rogers, who led the experiment as part of his PhD research, under the supervision of Morris.

Pinched off vortex rings in a reacting plume
A vertical tube of viscous solution contains stable reactants for the Iodate Arsenous Acid reaction. An indicator makes the solution red. Reaction is triggered at the base of a small tube at the bottom, leading to a growing plume that sheds accelerating vortex rings. No fluid is injected: all the buoyancy is created by the reaction itself.   The process is analogous to the nuclear deflagration leading to the detonation of a type Ia supernova.  Experiment by Michael Rogers.

“It is extremely difficult to observe the inside of a real exploding star light years away so this experiment is an important window into the complex fluid motions that accompany such an event,” Morris explains. “The study of such explosions in stars is crucial to understanding the size and evolution of the universe.”

In addition to Morris and Rogers, the research team included Abdelfattah Zebib from Rutgers. The work was funded by the Natural Sciences and Engineering Research Council of Canada.

Citation: 'Autocatalytic Plume Pinch-Off', Michael C. Rogers, Abdel Zebib, and Stephen W. Morris 
Phys. Rev. E (to be published)