topic Research

High-energy physics

Four fundamental forces keep the smallest known particles "moving on". Particle physics studies how these elementary particles interact. Accelerators in which particles gain very high energies are used therefore, that's why this field is often referred to as "High-energy physics" ...

Particle physics studies the smallest pieces in our world. It looks for the innermost structures of matter, space and time as well as for the laws which are the basis for the fundamental forces in the universe. After all we know today, leptons and quarks are the smallest elements in our world. Four fundamental forces exist between them. In addition to the well-known gravity and electro-magnetism, there is the weak force which makes cores of atoms decay emitting particles (radioactivity), and the strong force which keeps quarks in nucleons and nucleons in cores of atoms.

These scientific findings could only be gained because increasingly stronger microscopes in the form of big particle accelerators could be built for high-energy physics in the last century. It is essential to create elementary particles of very high energy in order to be able to enter the smallest dimensions of our world. Such facilities are enormously challenging for engineers and physicists and their construction is linked to technological innovations.

In spite of all the valuable knowledge gained in recent decades, a number of basic questions are still unanswered.

• Why do elementary particles have the mass they have?
• Why are there precisely three families of particles and why does the charge of a proton exactly equal that of an electron?
• Is there a universal interaction which is the origin of the four known fundamental forces?
• Are there still unknown forms of matter, e.g. a new world of super-symmetric particles? Are they the explanation for dark matter in the universe?
• Of what nature is the dark energy which makes the universe expand more rapidly?
• Are there hidden dimensions in addition to the known three spatial dimensions?

The inauguration of the Large Hadron Collider (LHC ) at CERN, Geneva (Switzerland) and its large detectors took place in October 2008 at CERN . In this circular collider of about 30 km circumference, protons are accelerated up to the highest energy ever reached in a laboratory. High-energy physics is on the cusp of new discoveries. Thousands of particle physicists from all over the world are using the four large detectors of the LHC (ALICE, ATLAS, CMS and LHCb) to explore the innermost structure of matter and the fundamental forces at so far unreachable energies and search for new, so far unknown particles. To benefit from the physics potential of the LHC, further efforts in research and development on an upgrade of the accelerating machine and the detectors are planed for the upcoming years. Worldwide strategic planning  and design studies for the next generation accelerators beyond the LHC are taking place.

Particle physics uses also complementary methods to search for new insights. Utilizing high precision experiments at lower energies enables searches for deviations from standard model  expectations in the area of flavour or neutrino physics.

Large-scale equipment and Institutions

DESY, Hamburg

• Tier2 center and National Analysis Facility for LHC experiments
  
•  National Analysis Facility for LHC experiments
• HERA with the experiments: H1, ZEUS and HERA-B (HERA data taking concluded in 2007)

• GridKA: Grid Computing Center Karlsruhe

CERN, Geneva

• ATLAS: A Toroidal LHC ApparatuS
• CMS: Compact Muon Solenoid
• LHCb: Large Hadron Collider beauty experiment
• NA62: Rare kaon decays
  

LNGS, Gran Sasso

• OPERA: neutrion oscillations

KEK, Tsukuba

• Belle II: Preparation for a high luminosity heasy flavour experiment

Research institutions (with BMBF funding)