16 June 2014

The ALICE group at NBI receives 6½ million kroner to research primordial soup

The ALICE group at the Niels Bohr Institute has received a grant of 6½ million kroner from the Danish Council for Independent Research | Natural Sciences to research the universe’s primordial state using collisions between heavy atomic nuclei at the LHC at CERN. 

Professor Jens-Jørgen Gaardhøje, head of the research group, ALICE at the Niels Bohr Institute.

Shortly after the Big Bang the universe consisted of a dense ‘primordial soup’ (called Quark Gluon Plasma) of the fundamental particles, quarks, gluons, leptons, photons, etc. possessing tremendous energy. After a millionth of a second, when the temperature had fallen to around 2000 billion degrees, the quarks and gluons were trapped in protons and neutrons, which make up the atomic nuclei in the matter the universe is now comprised of.

But what detailed properties of the strong force caused the universe to be created and look as we know it? What are the properties of the Quark Gluon Plasma and thus the early universe? How and why are quarks inextricably bound together in groups of three? What does the phase diagram for quark matter look like? Do gluon condensates exist? These are some of the questions that the Danish high energy physics group, ALICE, at the Niels Bohr Institute are trying to solve.

The experiments are carried out using the Large Hadron Collider (LHC) at CERN, the European Organization for Nuclear Research in Geneva in Switzerland, a 27 km long subterranean and superconducting  particle accelerator, and the gigantic ALICE multidetector which records thousands of particles originating from collisions between protons, protons and nuclei and between nuclei.

“The LHC at CERN is starting up at full energy early 2015 and will, for the first time,  reach energies of 5.5 TeV per particle pair in collisions between heavy nuclei of lead. We expect that up to 35,000 particles and antiparticles will be formed in each lead on lead collision and exist as a little mini-universe for approximately 10-23 second. This will lead to the creation of the highest energy density ever produced by man and constitute a unique test platform for studying the Quark Gluon Plasma and the strong interaction that binds the quarks together in the subatomic particles,” explains Professor Jens-Jørgen Gaardhøje, head of the research group, ALICE.

The grant of nearly 6½ million kroner will make it possible to hire two postdocs and two PhDs to carry out the first and basic measurements and first  studies of the reaction dynamic and  collective properties of the Quark Gluon Plasma in this entirely new energy range. The experiments will be carried out using the Danish built detectors in the ALICE experiment at the LHC at CERN which extend the experiments kinematical reach significantly.