ATLAS Experiment - History

History

The ATLAS collaboration, the group of physicists who built and now run the detector, was formed in 1992 when the proposed EAGLE (Experiment for Accurate Gamma, Lepton and Energy Measurements) and ASCOT (Apparatus with Super Conducting Toroids) collaborations merged their efforts to build a single, general-purpose particle detector for the Large Hadron Collider. The design was a combination of the two previous experiments, and also benefitted from the detector research and development that had been done for the Superconducting Supercollider. The ATLAS experiment was proposed in its current form in 1994, and officially funded by the CERN member countries in 1995. Additional countries, universities, and laboratories joined in subsequent years, and further institutions and physicists continue to join the collaboration even today. Construction work began at individual institutions, with detector components then being shipped to CERN and assembled in the ATLAS experiment pit from 2003.

Construction was completed in 2008 and the experiment detected its first single beam events on 10 September of that year. Data taking was then interrupted for over a year due to an LHC magnet quench incident. On 23 November 2009, the first proton-proton collisions occurred at the LHC, at a relatively low injection energy of 450 GeV per beam. These collisions were successfully registered in ATLAS, which has been logging data ever since. All the while LHC energy has been increasing: 900 GeV per beam at the end of 2009, 3,500 GeV for the whole of 2010 and 2011 and finally 4,000 GeV per beam in 2012. After a Long Shutdown in 2013 and 2014 the accelerator will double its current energy.