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Lasers help recreate supernova explosions in lab

June 2, 2014
Courtesy of STFC
and World Science staff

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.


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Researchers have used lasers to recreate scaled supernova explosions, some of the most energetic events in the universe. The 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. To recreate a supernova explosion in the laboratory an international team, led by researchers from the University of Oxford, used the laser 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 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. lab