IIHE invited seminar: Exploring the QCD phase diagram at the LHC with ALICE
by
Prof.Johanna Stachel(Physikalisches Institut der Universitaet Heidelberg)
→
Europe/Brussels
Universe
Universe
Description
The theory of strong interaction, quantum-chromo-dynamics (QCD), predicts for high temperature and density a new state of matter in which the
confinement of quarks and gluons is lifted. This state, the
quark-gluon-plasma, existed in the early universe after the
electro-weak phase transition up to about 10 microseconds. In the past
25 years accelerator-based experiments have been conducted in order to
recreate this state of matter for a short time. The ideal tool are
collisions of heavy nuclei at energies as high as possible. Now with
the Large Hadron Collider (LHC) at CERN an entirely new energy regime
is accessible.
I will discuss two aspects of the data: (i) Experimental knowledge
about the phase bounary between ordinary hadronic matter and the
quark-gluon plasma. This is based on the measured yields of various
hadronic species. (ii) Evidence for deconfinement. This comes from
the production of charmonia as a function of center of mass energy and
centrality of the collision. The LHC data will be put into perspective
vis-a-vis the results from lower energies.