alice a l arge i on c ollider e xperiment at the lhc
Post on 20-Dec-2015
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TRANSCRIPT
The Big Bang…• At the root of all matter there are
quarks, held together by “gluons”• A millionth of a second after the big
bang, all the matter was squeezed into a small space, around 300m wide
• In this hot dense environment, strong force was too low to hold the quarks together
• The quarks and gluons were free, in a new kind of matter called “quark-gluon plasma”
What happened next?
• After 10-23seconds, the plasma cooled, particles began to form and everything expanded out with a lot of energy!
ALICE and the “mini-fireball”
• ALICE collides Pb ions which have been accelerated to 99% of the speed of light, so they hit each other with very high energies!
• But how can scientists see the QGP behind all the particles?
ALICE uses the Solenoid Magnet from LEP: 14 metres high, each door weighs 350 tonnes!
The ALICE detector
Torroidal Magnet – Europe’s Biggest!
Time Projection Chamber – The biggest ever built!
Lead Tungstate Crystals for the Silicon Vertex TrackerThe ALICE detector in construction:
Outside: The Large Solenoid Magnet with Muon Detectors sandwiched in between the layers of iron
Middle layer: Torroidal magnet
Centre of the detector: Calorimeters, Trackers and Vertex Detectors