particle accelerators

A bird dropping a baguette temporarily shut down the $5 billion Large Hadron Collider earlier this month. But scientists have a good feeling about the restart, which is slated for Friday, the The Guardian reports.

Over the weekend, Cern ran particle beams through the Large Hadron Collider for the first time since it was shut down last September. After a helium leak caused magnets to overheat, operations at the LHC were suspended for cleanup and repairs. After tests on October 23 and 25, scientists hope to have the LHC running again in full by November.

While the LHC's in the shop for repairs from its massive breakdown last September, an older particle accelerator might beat them to finding the Higgs boson, the fundamental particle thought to give matter mass.

At a conference last week, Tevatron physicists threw down the gauntlet, vowing that by 2011, the Tevatron accelerator (located at Fermi National Accelerator Lab outside Chicago) will be able to definitively prove or disprove the existence of the Higgs boson.

The National Synchrotron Light Source was commissioned in 1982, and it remains one of the world's leading experimental light sources. But with so much of today's science happening on the nano-scale, the '80s technology doesn't quite have the resolution to keep up. The $912 million NSLS-II, which is slated to go live in 2015 -- if funding comes through -- will have the most concentrated, brightest radiation beam in the world: 10,000 times brighter than its predecessor -- not to mention 10 billion times brighter than the sun.

The purpose of the LHC is to get lots of protons moving very, very fast. The magnet system is the core piece of technology that makes this happen. More than 1,200 magnet sections, each weighing 10 tons, bend proton beams through vacuum pipes around the 17-mile-long underground tunnel near Geneva. Since these protons are going so fast—99.9999991 percent of the speed of light—superconducting coils of niobium and titanium must produce a magnetic field that’s about 200,000 times as strong as Earth’s to bend them.

The proton is a persistent thing. The first one crystallized out of the universe's chaotic froth just 0.00001 of a second after the big bang, when existence was squeezed into a space about the size of the solar system. The rest quickly followed. Protons for the most part have survived unchanged through the intervening 13.8 billion years—joining with electrons to make hydrogen gas, fusing in stars to form the heavier elements, but all the while remaining protons. And they will continue to remain protons for billions of years to come.

Well, it's never a great idea to stand next to a machine that could create black holes, but the magnets that steer the proton beams around the planet's most powerful particle accelerator would probably spare you from excess radiation. Then again, there is the off chance that some 300 trillion protons could erupt from the device and kill you on the spot.

THE PAPER: A Rotating Black Ring Solution in Five Dimensions


THE JOURNAL: Physical Review Letters, March 11, 2002


THE AUTHORS: Roberto Emparan and Harvey S. Reall


THE GIST: If you know anything about black holes, you probably think their shape can only be spherical. But they might also be shaped like tiny doughnuts. And if that's true, we might be living in a five-dimensional universe.