Japan: World’s newest atom smasher circulates beams for the first time


March 3, 2016 – The SuperKEKB particle accelerator has been developed in Japan. Richland’s Pacific Northwest National Laboratory plays a major role in the scientific findings at the atom smasher.

Scientists are hopeful that it would do a better job as compared to similar accelerators at forming rare particles, probably even dark matter that may give information over why there appear to be exceptions to the standard model of particle physics. They are hunting the ‘new physics’, beyond the normal model that has been ruling in the past.


For the first time in 5 years, particle physicists are on the cusp of having two major collider facilities running. Researchers have succeeded in circulating beams in a collider called SuperKEKB, officials at Japan’s High Energy Accelerator Research Organization (KEK) in Tsukuba announced today. If all goes as planned, researchers using SuperKEKB will start smashing electrons into positrons next year and join their counterparts working on the world’s biggest atom smasher, the Large Hadron Collider (LHC) in Switzerland, in the hunt for new physics. (A third collider, the Relativistic Heavy Ion Collider at Brookhaven National Laboratory in Upton, New York, focuses more on a type of nuclear physics.)

“It’s the first new accelerator since 2008,” when the LHC turned on, says Thomas Browder, a physicist at the University of Hawaii, Manoa, and spokesperson for the 600 physicists working on the Belle II particle detector, which will be fed by SuperKEKB. The LHC has been particle physicists’ lone collider since the United States shutdown its Tevatron collider at Fermi National Accelerator Laboratory in Batavia, Illinois, in 2011.

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Previous week, the accelerator circulated a beam of electrons having a speed roughly that of light via a narrow tube across the about 2-mile circumference of its major ring 32 feet underground. It sent a beam of positrons in the other direction surrounding the tube, on February 10.

Such circulating particles across many revolutions of an accelerator are known as ‘first turns’, which are a main step in commissioning the accelerator.

In the approaching year, when the accelerator will start operating, the beams of electrons and positrons will get compressed and smash together head-on in a smaller region as compared to any other accelerator of the kind has done so far. The collisions will take place in an area just 100 nanometers high, which is tinnier than a hardly visible dot of text.

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The outcome must be 40 to 50 times the number of collisions formed by similar accelerators, like the Japan accelerator prior to its got upgraded. More the number of collisions more will be the chances of important observations.

The energy of SuperKEKB will be tuned to produce copious particles known as B mesons, each of which contains a massive particle called a bottom quark and a light antiquark. Thanks to the weirdness of quantum mechanics, the properties of a B meson depend on other particles flitting in and out of “virtual” existence within it. So if there are new particles beyond the standard model, then their ghostly presence within the B meson might skew the meson’s properties from the predictions of the standard model—even if those new particles are too heavy to produce directly at the LHC.

SuperKEKB is actually a $275 million upgrade of its older KEK B Factory (KEKB), which ran from 1999 to 2010. It consists of two rings, each 3 kilometers in circumference. Electrons circulating in one ring will be accelerated up to an energy of 7 gigaelectron-volts (GeV).

Positrons, electrons’ antimatter counterparts, will travel in the other ring at an energy of up to 4 GeV. To boost the collision rate far above KEKB’s best, physicists replaced a significant proportion of the accelerator’s magnets as well as much of the beam piping and made numerous other tweaks. “The objective was to make the beam smaller while increasing the current,” says Kazunori Akai, a KEK physicist. The electrons and positrons will smash together within the Belle II detector, which is still under construction.

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