The world of ATLAS The 1800 scientists from 164 universities and laboratories collab- orating on ATLAS represent 35 countries and all the world’s populated continents. In 2008 the fi rst LHC proton beams will collide in the centre of ATLAS and for the next 10-15 years a huge amount of data will be collected and analysed in universities and laboratories all over the world.
Inserting the supercon- Scientists and engineers ducting solenoid magnet come from all over the into the barrel cryostat of world to work on ATLAS the electromagnetic calo- (right). rimeter (below).
The control room, where physicists from many institutes come to monitor the operation of the experiment (left).
The ATLAS Experiment The large international ATLAS collaboration provides a powerful environment for exploration in particle physics. It succeeds by splitting its work into separate projects in which smaller working groups can make substantial contributions. Components come to CERN, near Geneva, from all ATLAS over the world to be integrated in the giant detector.
Members of the team The muon chambers are ATLAS is one of four major experiments that assembling the pixel produced in ten diff erent will enter new territory in the exploration of detector which pinpoints countries before being matter, energy, space and time when the Large the tracks of particles installed in the experiment Hadron Collider begins operation at CERN. (left). (below). Designed to fi nd out why the Universe is like it is today, ATLAS will probe more deeply into matter than ever before and explore new fundamental processes.
Unlocking Nature’s secrets by investigating Assembly of the Semicon- particle collisions with ATLAS will be an ductor Tracker (left). unprecedented scientifi c and technological challenge. The ATLAS experiment is being conducted by a collaboration of scientists from 35 countries around the world. The detector they are building is not only complex but CERN The vast amount of data from the proton collisions will be used to study a wide variety of research also very big — it will be the largest-volume European Organization topics, by scientists and students in their home institutions. Some 400 students worldwide are partici- for Nuclear Research pating in ATLAS, constructing the detector and preparing for collection and analysis of the data. detector ever constructed for particle physics. CH-1211 Geneva, Switzerland
Communication Group, June 2007 CERN-Brochure-2007-001-Eng The ATLAS website contains further information on the organization, the detector, the physics, the LHC and the partici- pating university and laboratory groups.
http://atlas.ch http://atlas.ch ATLAS Physics The ATLAS detector consists of four major components: The particles from a collision event leave tracks and deposit energy in the detector. This is how an event would look in the detector. Inner Detector The unknown Measures the momentum ATLAS brings experimental physics into new terri- of each charged particle. tory. Most exciting is the completely unknown sur- ATLAS and the LHC prise — new processes and particles that would ATLAS will observe dramatic head-on change our understanding of energy and matter collisions of pairs of protons whose to- and of the basic forces that have shaped our uni- tal energy is 14 TeV. The protons will be Calorimeters verse since the beginning of time. Are there, for example, extra dimensions of space or mini- accelerated to these high energies by Measure the energies black holes? the Large Hadron Collider (LHC) — an carried by the particles. underground accelerator ring 27 km in circumference. The LHC is fi lled with superconducting magnets to steer and focus the protons in beams that repeatedly circle the ring. The ambi- Dark matter tious experimental programme of ATLAS will shed light on many unan- LHC will recreate the con- swered questions about the origins of ditions of the universe matter and the fundamental forces of just after the Big Bang nature. to understand why the universe is like it is today. The particle collisions It will investigate why the matter of the uni- Measuring 46 m long and 25 m high, verse is dominated by the ATLAS detector is the largest and an unknown type called one of the most elaborate particle Muon Spectrometers Identify and measure the dark matter. If the con- physics experiments ever designed. momenta of muons. stituents of dark matter The head-on collisions of protons at its are new particles, ATLAS centre leave debris that will reveal new should discover them particles and new processes in the in- and elucidate the mys- terior of matter. tery of dark matter. Various layers of the detector will track the trajectories of the charged parti- cles and measure the energies of most charged and neutral particles. The cur- vature of particle tracks in the magnet- Antimatter ic fi eld will allow the momentum and electric charges to be determined. Out At the very beginning of the universe, equal of nearly 1000 million collisions each amounts of matter and antimatter existed. second, only a few will have the special Mass If matter and antimatter were exact mir- ror images of each other, they would have characteristics that might lead to new Why do fundamental particles have such completely annihilated to leave only en- discoveries. The trigger system selects diff erent masses? Two of the greatest ergy. But why was some of the matter left such events for recording and avoids mysteries are how particles gain mass over to create galaxies, the solar system storing immense amounts of unneces- Magnet System and how mass and energy are related. To with our beautiful planet, and us? ATLAS sary information. Bends charged particles for momentum explain these mysteries, theories predict will explore the tiny diff erence that exists measurement. The solenoid magnet a new particle, the Higgs particle. If this between matter and antimatter. surrounds the inner detector. Arrows particle exists, ATLAS will discover it and point to toroid magnets. provide great insight into the problem of Detector masses. ATLAS Physics The ATLAS detector consists of four major components: The particles from a collision event leave tracks and deposit energy in the detector. This is how an event would look in the detector. Inner Detector The unknown Measures the momentum ATLAS brings experimental physics into new terri- of each charged particle. tory. Most exciting is the completely unknown sur- ATLAS and the LHC prise — new processes and particles that would ATLAS will observe dramatic head-on change our understanding of energy and matter collisions of pairs of protons whose to- and of the basic forces that have shaped our uni- tal energy is 14 TeV. The protons will be Calorimeters verse since the beginning of time. Are there, for example, extra dimensions of space or mini- accelerated to these high energies by Measure the energies black holes? the Large Hadron Collider (LHC) — an carried by the particles. underground accelerator ring 27 km in circumference. The LHC is fi lled with superconducting magnets to steer and focus the protons in beams that repeatedly circle the ring. The ambi- Dark matter tious experimental programme of ATLAS will shed light on many unan- LHC will recreate the con- swered questions about the origins of ditions of the universe matter and the fundamental forces of just after the Big Bang nature. to understand why the universe is like it is today. The particle collisions It will investigate why the matter of the uni- Measuring 46 m long and 25 m high, verse is dominated by the ATLAS detector is the largest and an unknown type called one of the most elaborate particle Muon Spectrometers Identify and measure the dark matter. If the con- physics experiments ever designed. momenta of muons. stituents of dark matter The head-on collisions of protons at its are new particles, ATLAS centre leave debris that will reveal new should discover them particles and new processes in the in- and elucidate the mys- terior of matter. tery of dark matter. Various layers of the detector will track the trajectories of the charged parti- cles and measure the energies of most charged and neutral particles. The cur- vature of particle tracks in the magnet- Antimatter ic fi eld will allow the momentum and electric charges to be determined. Out At the very beginning of the universe, equal of nearly 1000 million collisions each amounts of matter and antimatter existed. second, only a few will have the special Mass If matter and antimatter were exact mir- ror images of each other, they would have characteristics that might lead to new Why do fundamental particles have such completely annihilated to leave only en- discoveries. The trigger system selects diff erent masses? Two of the greatest ergy. But why was some of the matter left such events for recording and avoids mysteries are how particles gain mass over to create galaxies, the solar system storing immense amounts of unneces- Magnet System and how mass and energy are related. To with our beautiful planet, and us? ATLAS sary information. Bends charged particles for momentum explain these mysteries, theories predict will explore the tiny diff erence that exists measurement. The solenoid magnet a new particle, the Higgs particle. If this between matter and antimatter. surrounds the inner detector. Arrows particle exists, ATLAS will discover it and point to toroid magnets. provide great insight into the problem of Detector masses. The world of ATLAS The 1800 scientists from 164 universities and laboratories collab- orating on ATLAS represent 35 countries and all the world’s populated continents. In 2008 the fi rst LHC proton beams will collide in the centre of ATLAS and for the next 10-15 years a huge amount of data will be collected and analysed in universities and laboratories all over the world.
Inserting the supercon- Scientists and engineers ducting solenoid magnet come from all over the into the barrel cryostat of world to work on ATLAS the electromagnetic calo- (right). rimeter (below).
The control room, where physicists from many institutes come to monitor the operation of the experiment (left).
The ATLAS Experiment The large international ATLAS collaboration provides a powerful environment for exploration in particle physics. It succeeds by splitting its work into separate projects in which smaller working groups can make substantial contributions. Components come to CERN, near Geneva, from all ATLAS over the world to be integrated in the giant detector.
Members of the team The muon chambers are ATLAS is one of four major experiments that assembling the pixel produced in ten diff erent will enter new territory in the exploration of detector which pinpoints countries before being matter, energy, space and time when the Large the tracks of particles installed in the experiment Hadron Collider begins operation at CERN. (left). (below). Designed to fi nd out why the Universe is like it is today, ATLAS will probe more deeply into matter than ever before and explore new fundamental processes.
Unlocking Nature’s secrets by investigating Assembly of the Semicon- particle collisions with ATLAS will be an ductor Tracker (left). unprecedented scientifi c and technological challenge. The ATLAS experiment is being conducted by a collaboration of scientists from 35 countries around the world. The detector they are building is not only complex but CERN The vast amount of data from the proton collisions will be used to study a wide variety of research also very big — it will be the largest-volume European Organization topics, by scientists and students in their home institutions. Some 400 students worldwide are partici- for Nuclear Research pating in ATLAS, constructing the detector and preparing for collection and analysis of the data. detector ever constructed for particle physics. CH-1211 Geneva, Switzerland
Communication Group, June 2007 CERN-Brochure-2007-001-Eng The ATLAS website contains further information on the organization, the detector, the physics, the LHC and the partici- pating university and laboratory groups.
http://atlas.ch http://atlas.ch