Detectors of LHC experiments ATLAS and CMS

Takahiko Kondo


A Higgs-like paricle was discovered in 2012 by two energy-frontier experiments ATLAS and CMS at LHC. These two detectors were designed in 1990's and have been constructed for over 10 years and commissioned successfully in 2008. LHC provides about 40 pp collinsions every 25 ns. Number of secondary particles in each pp collisions is an order of 100. Therefore all detectors must be segmented into fine elements with very fast response time to minimize signal overlaps in space as well as in time. In addition, the total radiation dose near the beam pipe is reaching to an order of 10 MRads in 10 years of LHC operation. Tracking detectors using silicon crystals can tolerate such high radiation environments. Electromagnetic and hadronic calorimeters hermetically cover the interaction point in order to measure the total transvere energies. Near perfect hermeticity of calorimetry is required for measuring missing-Et, one of key variables for physics reconstruction. In this talk, I present outline of tracking and calorimeter devices used in ATLAS and CMS. In addition, basic principles of silicon crystal detectors are briefly presented including radiation effects.



Short Bio

Takahiko Kondo is a Professor Emeritus of KEK. After obtaining his Ph.D. in high energy particle physics in 1973 from the University of Tokyo, he was a research associate of University of Pennsylvania and then at Fermilab. He became an assistant Professor at KEK in 1981. While he worked for the construction of the VENUS detector at Tristan project at KEK, he involved in R&D of detector development for SSC (Superconducting Super Collider), the project developed at USA in 1980's, started in 1989 and cancelled in 1993. Since 1994 he has been working as a member of ATLAS collaboration for LHC.