How big is the big hadron collider

LHC - facts and figures

The largest machine in the world ...

The last LHC dipole magnet is lowered into the tunnel.
Photo: CERN

The Large Hadron Collider LHC at CERN is the most powerful particle accelerator in the world. Its exact circumference is 26,659 meters. A total of 9,300 magnets are housed inside. The LHC's cooling system is the largest refrigerator in the world. All magnets in the LHC are pre-cooled to -193 ° C (80 K) with 10 080 tons of liquid nitrogen before they are filled with around 60 tons of liquid helium and then cooled down to -271.3 ° C (1.9 K).

The fastest proton racetrack on our planet ...

When the LHC is running at maximum power, the protons race 11 245 times per second through the LHC accelerator ring and reach almost the speed of light. Two proton beams circle with a maximum energy of 7 tera-electron volts (TeV) and collide with one another with 14 TeV. In total, there will be up to a billion proton-proton collisions per second, more than ever before.

The emptiest space in the solar system ...

So that the particle beams do not collide with gas atoms in the LHC accelerator, they fly in the two beam pipes in an ultra-high vacuum. These tubes are as empty as interplanetary space. The internal pressure in the LHC is 10-13 atm, that's ten times less than the pressure on the moon.

The hottest place in the galaxy, but colder than space ...

The LHC is a machine of extremes of hot and cold. When two proton beams collide, they generate temperatures 100,000 times higher than those inside the sun, but concentrated in the smallest of spaces. In contrast, the surrounding magnets are colder than space!

The largest and most modern detectors ever built ...

Welding work on a dipole magnet for the LHC.
Photo: CERN

So that the up to one billion proton collisions per second can be recorded and stored, physicists and engineers have built enormous devices that measure the trajectories of the particles with a precision in the micrometer range. The particle densities that occur in the collisions at the LHC exceed anything that has come before. For this reason, the detectors had to be built with a very high resolution. The number of channels to be read out, via which the information is routed from the detector to the outside, also exceeds the size of existing systems many times over. The detectors in the LHC contain sophisticated electronic systems that measure the passage of a particle with a precision of a few thousandths of a millimeter.

The most powerful supercomputer ...

The data recorded by the LHC detectors would fill several hundred thousand DVDs a year. In the coming years, thousands of physicists all over the world will evaluate and analyze this data. To make this possible, tens of thousands of computers around the world are interconnected in a computer network, the grid. Although the grid was developed for the LHC, it can also be used in other scientific areas where large amounts of data have to be processed.