World’s Largest Superconducting Magnet

The Barrel Toroid superconducting magnet is part of the ATLAS detector, one of the four big particle experiments on the Large Hadron Collider (LHC), currently under construction at the CERN Laboratory in Switzerland. Among the questions ATLAS will focus on are why particles have mass, what the unknown 96% of the universe is made of, and why nature prefers matter over antimatter. Some 1800 scientists from 165 universities and laboratories in 35 countries are building the ATLAS detector and preparing to study the effects of head-on collisions of high energy protons. The protons are accelerated in the 27 km (~17 mi.) long accelerator ring of the underground collider and then steered by the magnet to collide in the center of the ATLAS detector. The energy density resulting from these high energy collisions is similar to the particle collision energy that followed the Big Bang by less than a billionth of a second.

Measuring 5 m x 25 m and weighing 100 tons, this behemoth is the largest superconducting magnet ever built. The Toroid is able to create a magnetic field of about 4 T (tesla) while an electrical current of more than 21,000 amperes pass through its eight gigantic coils. Although it will be more than a year before the LHC will be completed, the Toroid superconducting magnet was tested for the first time on the 9th of November 2006. 

More information on the Barrel Toroid superconducting magnet from the ATLAS CERN website.