ATLAS (A Toroidal LHC ApparatuS) is a detector in construction at CERN for one of the two general-purpose proton-proton experiments at the Large Hadron Collider. The ATLAS experiment is prepared by a large collaboration of 150 institutions from 34 countries. At present the ATLAS experiment entered the phase of commissioning and installation at LHC, and will be ready for data taking in 2007.

The major components of the ATLAS detector are: the inner tracker, the calorimeter system, the muon spectrometer and the magnetic system, completed by a complex project for trigger and data acquisition and computing based on Grid technology.

The ATLAS experiment will improve our fundamental understanding of matter and forces. A prime goal of ATLAS is to explain the origin of mass by the discovery of the Higgs boson, but the detector will allow also the investigation of many other problems in particle physics (top physics, B-physics, supersymmetry, production of exotic particles, etc).

The National Institute of Physics and Nuclear Engineering participates in the ATLAS Collaboration since 1993.

The Romanian ATLAS Group activities are partially supported by Romanian National Authority for Scientific Research through the contract 15 EU / ATLAS / 6.04.2009 ( click here for details ) (CO-IFIN-HH, P1-ITIM Cluj-Napoca, P2-Tech. Univ.-Bucharest), responsible person Sanda Dita.