Atlas Detector ATLAS Components Discovers headon collisions of

Atlas Detector

ATLAS Components Discovers head-on collisions of protons of extraordinarily high energy

Inner Detector Measures the momentum of each charged particle

Calorimeter Measures the energies carried by particles

Muon Spectrometer Identifies and measures muons

Magnet System Bends charged particles for measuring momentum

Semiconductor Tracker (SCT) Measures: • Momentum • Impact parameters • Vertex position

Pixel Detector Determines: • Impact parameter resolution • Ability of the Inner Detector to find short- lived particles such as B hadrons

Transition Radiation Tracker (TRT) Assists in electron identification Uses a system which includes Xenon gas and “straws” • Each straw is 4 mm in diameter and equipped with a 30 μm diameter gold-plated W-Re wire. • The maximum straw length is 144 cm in the barrel, which contains about 50 000 straws. • Endcaps contain about 320, 000 radial straws.

ATLAS: • Is 45 meters long. • Is more than 25 meters high. • Weighs about 7, 000 tons. Is half as big as the Notre Dame Cathedral in Paris. Weighs the same as the Eiffel Tower.

ATLAS vs. LHC: • Lies in a tunnel 27 kilometers (17 miles) in circumference. • Is 175 meters (574 ft. ) beneath the Franco-Swiss border. • Workers include over 10, 000 scientists and engineers from over 100 countries.

Citations • http: //atlas. ch/detector. html • http: //atlas. ch/inner_detector 3. html • http: //visits. web. cern. ch/visits/guides/tools/man ual/english/atlas. html • http: //www. boston. com/bigpicture/2008/08/the_l arge_hadron_collider. html