Large Hadron Collider

1
Large Hadron Collider

• Venkat Kaushik
• U. Arizona / ATLAS Expt. At C.E.R.N.
• January 28, 2008

2
Some Unanswered Questions

• What is the origin of mass?
• Visible matter makes up about 3 of our universe
• What makes up the rest of 97 of our universe?
• Dark Matter / Dark Energy
• What did the universe look like moments after
  big-bang?
• Existence of Quark-Gluon plasma
• Why do we exist?
• Why did nature favor matter over anti-matter
• Are there any hidden dimensions?
• We know of three spatial dimensions and time
• Why are there three generations of matter?

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Exploring The Early Universe
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The Standard Model of Particle Physics
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Particle Accelerators Principle
Lorentz Force
Matter Wave

• How to create (massive/unstable) particles in a
  lab experiment?
• E mc2 E Energy, m Rest mass, c Speed
  of light
• Recipe
• Take a charged particles (e.g., electrons,
  positrons, protons)
• Accelerate them in electromagnetic field (large
  Kinetic energy)
• Collide a single beam to a target / Collide two
  beams
• LINAC or Synchrotron or a combination of both

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What does LHC stand for?

• Why Large?
• Maximum collision energy one can obtain is a
  function of
• Size of the accelerator ( larger size means
  larger energy of collision)
• LHC synchrotron is 27 km (17 miles)
  circumference , 100 m (6 story's) underground
  across the French / Swiss border.
• Why Hadron?
• LHC uses protons (H) and lead ions (Pb82) which
  are Hadrons
• Why Collider?
• Fixed Target
• Energy available to make new particles vBeam
  energy
• Colliding two beams
• Energy available to make new particles 2 x Beam
  energy
• Each beam has 7 TeV of energy. Energy available
  2 x 7 TeV 14 TeV

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The CERN Accelerator Complex
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Experiments at the LHC

• ATLAS
• A Toriodal LHC ApparatuS
• CMS
• Compact Muon Solenoid
• ALICE
• A Large Ion Collider Experiment
• LHCb
• Large Hadron Collider beauty
• TOTEM
• TOTal Elastic and diffractive cross section
  Measurement
• LHCf
• Large Hadron Collider forward

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ATLAS / CMS

• ATLAS
• Size 46 m long, 25 m high, 25 m wide
• Weight 7000 tons
• Location Meyrin, Switzerland
• Searching Origin of mass, forces
• Higgs Boson, Dark Matter, Extra dimensions
• Collaboration
• 1700 scientists
• 159 institutes in 37 countries
• http//atlas.ch/

• CMS
• Size 21 m long, 15 m high, 15 m wide
• Weight 12, 500 tons
• Location Cessy, France.
• Searching Origin of mass, forces
• Higgs Boson, Dark Matter, Extra dimensions
• Collaboration
• 2000 scientists
• 155 institutes in 37 countries
• http//cmsinfo.cern.ch/outreach/

10
ALICE / LHCb

• ALICE
• Size 26 m long, 16 m high, 16 m wide
• Weight 10,000 tons
• Location St. Genis-Pouilly, France.
• Searching for QUARK GLUON plasma
• Collaboration
• 1000 scientists
• 94 institutes in 28 countries
• http//aliceinfo.cern.ch/Public/

• LHCb
• Size 21 m long, 10 m high, 13 m wide
• Weight 5600 tons
• Location Ferney-Voltaire, France.
• Searching for why we exist !!
• why nature prefers matter over antimatter?
• Collaboration
• 650 scientists
• 48 institutes in 13 countries
• http//lhcb-public.web.cern.ch/lhcb-public/

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ATLAS Detector
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Particle Detectors Principle
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Computing Data Storage / Analysis
15, 000, 000 Gigabytes per year 1.7 million
dual layer DVDs (1 mile long !!)
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THE END!THANK YOU!
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Backup Slides

• Dark Matter / Dark Energy
• Annual cost of running LHC
• CERN Facts
• LHC Facts

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Dark Matter / Dark Energy
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Who pays for it?

• CERN consumes 800, 000 MWh of power per year
• Equivalent to power consumed by households in a
  city the size of Las Vegas, NV
• Yearly cost of running LHC 19 Million Euro 25
  Million USD
• Funded by member states (Energy mainly from
  France , some from Switzerland)
• Compare to 10 billion being spent by U.S. in
  Iraq per month

18
LHC Facts

• LHC is its own prototype
• There is no other machine that is like it. From
  drawing board to design and construction its the
  only one of its kind.
• Extremes
• Magnets are cooled by liquid nitrogen first and
  60 tons of liquid Helium to a temperature of
  -271.3?C (-456.3 F) colder than outer space !!
• 600 million proton-proton collisions per second
  in the tunnel cavity which is as empty as
  interplanetary space (ultra-high vacuum)
• 9300 magnets
• 1200 bending, rest are used in correction /
  focusing beam
• 8 Tesla magnetic field
• Over 150,000 times stronger than the earths
  magnetic field
• First envisioned in 1980s
• Competitor to the SSC in Texas, LHC construction
  approved in 1994.
• LHC construction timeline.
• First magnet installed (2005).
• Last magnet installed (2007).