High Energy AcceleratorsHigh Energy Accelerators

Dennis SilvermanDennis SilvermanPhysics and AstronomyPhysics and Astronomy

U. C. IrvineU. C. Irvine

SLAC B Meson FactorySLAC B Meson Factory Neutral BNeutral B00 mesons are composed of a u quark and a mesons are composed of a u quark and a

b antiquark.b antiquark. They live long enough to go some distance in the They live long enough to go some distance in the

detector, called BaBar.detector, called BaBar. They oscillate to their anti- BThey oscillate to their anti- B00 through annihilating through annihilating

to a Wto a W++ and W and W-- pair. pair. In this oscillation there is a discrepancy between In this oscillation there is a discrepancy between

particle and antiparticle rates.particle and antiparticle rates. This allows us to learn about such a discrepancy This allows us to learn about such a discrepancy

that allowed the universe to remain one part in a that allowed the universe to remain one part in a billion matter after matter and antimatter billion matter after matter and antimatter annihilated in the big bang.annihilated in the big bang.

A similar B factory called Belle is producing similar A similar B factory called Belle is producing similar results in Japan.results in Japan.

B – Anti-B pairs formed by e+ B – Anti-B pairs formed by e+ e-e-

AnnihilationAnnihilationB – anti-B pair created through virtual B – anti-B pair created through virtual

photonphoton e-

e+

b->anti-B

anti-b-> B

virtual photon

SLAC Accelerator – PEP SLAC Accelerator – PEP ringsrings

BaBar DetectorBaBar Detector

Typical collider detector Typical collider detector elementselements

Fermilab TevatronFermilab Tevatron Rings allow collisions of protons and anti-protons Rings allow collisions of protons and anti-protons

in their center of mass, each of 1TeV energy.in their center of mass, each of 1TeV energy. Included quarks and anti-quarks colliding at a Included quarks and anti-quarks colliding at a

typical 1/3 of a TeV each.typical 1/3 of a TeV each.

proton

Anti-proton

CDF (and D0) DetectorsCDF (and D0) Detectors

LHC at CERNLHC at CERN Large Hadron Collider at CERN GenevaLarge Hadron Collider at CERN Geneva 7 TeV protons on 7 TeV protons in their 7 TeV protons on 7 TeV protons in their

center of mass, 27 km long ring tunnelcenter of mass, 27 km long ring tunnel Cost of $2.5 billion to international Cost of $2.5 billion to international

collaboration, U.S. about $0.5 billion share, collaboration, U.S. about $0.5 billion share, including much manpowerincluding much manpower

Atlas and CMS detectorsAtlas and CMS detectors Capable of producing Higgs and SUSY Capable of producing Higgs and SUSY

particlesparticles Starting in 2007Starting in 2007

LHC Ring LayoutLHC Ring Layout

LHC Tunnel and AcceleratorLHC Tunnel and Accelerator

Cross Section of Two Beam Cross Section of Two Beam PathPath

Magnets Magnets

Atlas Detector – Five Stories Atlas Detector – Five Stories TallTall

Neutrino DetectorsNeutrino Detectors Large water detectorsLarge water detectors Charged particles produce Cherenkov light Charged particles produce Cherenkov light

conescones Detect atmospheric produced neutrinos from Detect atmospheric produced neutrinos from

cosmic rays, and their oscillationscosmic rays, and their oscillations Detect solar neutrinos and their oscillationsDetect solar neutrinos and their oscillations Detect supernova produced neutrinosDetect supernova produced neutrinos Search for proton decaySearch for proton decay Talk in the Fall from Hank SobelTalk in the Fall from Hank Sobel

Super-K (Kamiokande)Super-K (Kamiokande)

Super-KSuper-K 11,000 20 inch phototubes11,000 20 inch phototubes 50 kilotons of purified water50 kilotons of purified water In a deep mine In a deep mine Dimensions: 40 m diameter, 40 m Dimensions: 40 m diameter, 40 m

highhigh

New Phototube layoutNew Phototube layout

SNO (Sudbury Neutrino SNO (Sudbury Neutrino Detector)Detector)

1 kiloton of Canadian 1 kiloton of Canadian heavy water D20heavy water D20 7 kilotons of normal7 kilotons of normalwater surroundingwater surrounding 18 m sphere 18 m sphere surroundingsurrounding 10,000 phototubes10,000 phototubes