The Fast Way Around
To get those protons up to speed, LHC engineers had to build 17 miles’ worth of the coldest, emptiest place in the universe
Large Hadron Collider
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. A power supply feeds these magnets with 12,000 amps of current, and a constant flow of liquid helium keeps the entire machine just 1.9 degrees above absolute zero. The conditions are both colder and emptier than deep space.