The Large Hadron Collider By Kathleen McKay
What is the LHC? • The most powerful particle accelerator in the world. • A synchrotron (ring-shaped particle accelerator) • Built by the European Organization for Nuclear Research (CERN) • A part of the CERN accelerator complex
History of the LHC • The LEP (Large Electron-Positron Collider) • Built in the tunnels the LEP used to occupy • Approved by CERN Council in 1994 • Built 1996- 2008 • Opened April 5th 2008 • Technical difficulties • Magnetic failures and a helium leak • 2010 first successful experiment
What does it do? • It accelerates two beams of hadrons at 99% the speed of light. • Particles of Matter • Uses 9,600 magnets to collide the two beams at six sites around its circumference. • Observes and studies the collisions.
What it’s looking for… • A mini Big Bang • Atomic subparticles • Matter v. Antimatter • Dark Matter • The Standard Model • Higgs Boson Particle • String Theory • 11 dimensions • Supersymmetry
Six Collision Sites ATLAS CMS Compact Moun Solenoid General purpose Contained inside solenoid magnet Field is 100,000 times stronger than Earth’s • A Toroidal LHC ApparatuS • 46m long, 25m tall, 25m wide • Inner tracker • Detect & analyze momentum • Calorimeter • Measures energy by absorption, shows path • Mounspectrometer • Measures momentum of particles too heavy to be caught by calorimeter
Six Collision Sites cont. ALICE LHCb Large Hadron Collider beauty Search for antimatter Beauty/bottom quarks 20 meters of detectors around the site to catch the quarks • A Large Ion Collider Experiment • Studies the collisions of iron ions • Mounspectrometer • Time Projection Chamber (TPC) • Tracks particle trajectories
The Two Small Collision Sites TOTEM LHCf Large Hadron Collider forward Stimulates cosmic rays Tries to make experiments where naturally occurring cosmic rays can be observed and studied • TOTal Elastic and diffractive cross section Measurement • Measures the size of protons • Measures luminosity (how precisely an accelerator produces collisions)
How It Works • 27 km circumference • 100 m underground • 8 arches, 8 insertions • Insertions- long straight sections, control coming and going of particles • Injection • Beam dumping • Beam cleaning • 3 vacuum systems • Beam vacuum • Insulation for cryomagnets • Insulation for helium distribution line
Magnets 9,600 magnets Guides the particle beams into collisions and through insertions. 3 Kinds Quadrupole- focuses beam Accelerating Cavities- accelerate particles and keep them at constant speed Dipole- keep the beams going in a circle 8.33 T
Cooling System • Designed so that the magnets can conduct electricity with almost no resistance and generate a high enough magnetic field. • 120 tons of super fluid helium • 5 cryogenic ‘islands’ • Colder than outer space: 1.9 K (-456.25 F)
Collision Results • Quarks- subatomic particles • Gluon- mitigating force • Photons- particles of light • Positrons- the anti-particles to electrons • Muons- negatively charged, heavier version of electrons
LHC Computing Grid 150 million sensors in the LHC 700 megabytes of data per second 15 petabytes per year 2001- EDG (European Data Grid project) 2004- EGEE (Enabling Grid for E-sciencE) Divides the data into chunks to be analyzed separately Uses midware Uses identification and authorization procedures to keep the information safe.
Question 1 What does LHC stand for? • Luminosity Higgs Controller • Large Higgs Chamber • Low Helium Cryomagnet • Large Hadron Collider
Question 2 Who created the LHC? • CMS • CERN • TOTEM • EDG
Question 3 What are the names of the six detector sites? • CMS, ALICE, TPS, TOTEM, LEP, LHCb • LHCf, LEP, CMS, ATLAS, LHCb, SPS • ATLAS, CMS, ALICE, LHCb, TOTEM, LHCf • EDG, ATLAS, SPS, LEP, LHCf, CMS
Question 4 What does the LHC do? • Measures momentum of particles too heavy to be caught by calorimeter. • Guides the particle beams into collisions and through insertions. • Collides two beams of particles. • Measures energy of particles through absorption.
Question 5 What temperature are the magnets cooled to? • 1.9 K • 3.9 C • 4.8 K • -354.25 F