Supernovae are one of the rarest phenomena in the universe. These are gigantic explosions of big stars happening in a matter of hours (compared to their size measuring millions of kilometres). Such an explosion creates shockwaves of unimaginable energy. These shockwaves accelerate particles to very high velocities, close to the velocity of light! Scientists don’t know how those shockwaves accelerate subatomic particles to such high velocities. So, they created a supernova here!!
Well, not quite literally. All they did was a simulation. The researchers headed by Frederico Fiuza worked in the National Ignition Facility, a Department of Energy facility at the Lawrence Livermore National Laboratory in California. Here they shot a pair of the counter facing targets, namely carbon sheets, with a very high energy laser. This generated two plasma flows that collided to create a shockwave of the kind found in a supernova. This shockwave also accelerated electrons to near-light speeds. The interactions were observed using optical and X-Ray spectrographs.
But researchers still couldn’t observe how the shockwaves acted as accelerators. So they turned to computer simulations. These simulations by Anna Grassi, a co-author of the paper on this experiment, offered a possible solution. The shockwave was observed to produce a turbulent electromagnetic field. This could be the reason why electrons are accelerated to such speeds.
The team of researchers is continuing the experimental observations. They also say that in future, they may try observing protons accelerated by the shockwave to further strengthen the hypothesis.
Ref: Article at Nature
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