#accelerators

Quark-Gluon Plasma

First of all… What are quarks and gluons?

Quarks are tiny subatomic particles that make up the nucleons (protons & neutrons) of everyday matter as well as other hadrons. Gluons are massless force-carrying particles which are necessary to bind quarks together (by the strong force\interaction) so that they can form hadrons.

QGP (Quark-Gluon Plasma)

A tiny fraction of a second after the Big Bang, the universe is speculated to have consisted of inconceivably hot and dense quark-gluon plasma. QGP exists at such high temperatures (about 4 trillion Kelvin — 250,000 times warmer than the sun’s interior), that the quarks and gluons are almost free from colour confinement (in other words, they do not group themselves to form hadrons). QGP does not behave as an ideal state of free quarks and gluons, instead it acts like an almost perfect dense fluid.

It then took only a few micro-seconds until those particles were able to cool down to lower energies and separate to form nucleons. 

RHIC & ALICE

To study the properties of the early universe, physicists have created accelerators that essentially recreate quark-gluon plasma. The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (in Upton, NY) collides heavy ions (mainly gold) at relativistic speeds. This accelerator has a circumference of about 2.4 miles in which two beams of gold ions travel (one travels clockwise, and the other anticlockwise) and collide. The resulting energy from the collision allows for the recreation of this mysterious primordial form of matter.

ALICE (A Large Ion Collider Experiment) at CERN (in Geneva, Switzerland) is the only other current heavy ion collider experiment which studies QGP. However, instead of gold, ALICE uses lead ions.