Lasers help recreate supernova explosions in lab
- June 24, 2014
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Researchers are using lasers to recreate at a small scale what happens when stars explode.
The supernova blasts, triggered in various ways within dying stars, launch a shock wave that sweeps through vast reaches of space from the bursting star. But not all such explosions are alike. Some, such as Cassiopeia A which lies 11,000 light years from the Earth (a light-year is the distance light travels in a year), show puzzling, irregular shapes made of knots and twists.
The new work is being carried out at the Vulcan laser facility in the U.K., operated by the Science and Technology Facilities Council, a publicly-funded U.K. research organization.
A research team led by University of Oxford scientists used the facility to investigate what might cause these peculiar shapes. The team focused three laser beams onto a carbon rod, not much thicker than a hair, in a chamber filled with a thin gas. The enormous amount of heat generated by the laser – more than a few million degrees Celsius – made the rod explode, creating a blast that expanded through the gas.
It's “a great demonstration of the use of high power lasers for studying such astrophysical phenomena,” said Rob Clarke, who leads the Experimental Science group at the council's Central Laser Facility. “Our laser, engineering and scientific staff are used to designing highly complex experiments which enable us to perform experiments at these extreme conditions.”
In the experiments the dense gas clumps or gas clouds that surround an exploding star were simulated by introducing a plastic grid to disturb and introduce turbulence into the expanding blast wave, he added. “The experiment demonstrated that as the blast of the explosion passes through the grid it becomes irregular and turbulent, just like the images from Cassiopeia,” said Oxford's Gianluca Gregori, who led the study, published in the journal Nature Physics June 1.
Source : http://www.world-science.net/othernews/140602_supernova.htm