ALICE A Large Ion Collider Experiment

at the LHC

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

That’s all from me!

• All images not drawn or taken by me were taken from ALICE Public Pages:

http://aliceinfo.cern.ch/Public/index.html

Have a look there for more information!