National Institute for Subatomic Physics

Particle Physics

The installation of the Semiconductor Tracker (SCT), part of ATLAS, one of the detectors in the LHC. The SCT detects the path of the particles.
The control room of ATLAS at CERN in Geneva

Particle accelerators form the basis for this research discipline. When particles such as protons are accelerated and then allowed to collide with other particles, a lot of energy is released to make other new particles in accordance with Einstein's E=mc². For this purpose, various accelerators have been built; in Hamburg at DESY, in Geneva at CERN, and in Chicago at the Fermilab.

Large Hadron Collider

The Large Hadron Collider (LHC) is the most powerful particle accelerator ever built. The LHC is located in a circular tunnel with a length of 27 km, which lies 50 to 175 metres underground at CERN, just outside of Geneva. The accelerator has been designed to accelerate bundles of protons in opposite directions and to let these collide with each other. Protons with high energy move in a vacuum through the accelerator ring, guided by superconducting magnets, which are cooled by an enormous cryogenic system.

In 2008, the accelerator was commissioned and eventually it will allow protons with an energy of 14 Tera electron Volts (TeV) to collide. That is enough to simulate the origin of the universe just fractions of a second after the Big Bang. Beams of lead nuclei are also accelerated and collide with an energy of 1150 TeV. The intensity of the  beam is impressive in view of the fact that 600 million collisions a second take place.

A TeV is a unit for energy, used frequently in particle physics. One TeV is roughly equal to the energy of a flying mosquito. What makes the LHC so special is that this energy is compressed into a space that is a million million times smaller than a mosquito.

Nikhef's particle research:
ATLAS (currently only in Dutch)

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