Webpages tagged with «QGP»

The QGP behaves like a low-viscosity liquid and exhibits a collective, multi-harmonic azimuthally anisotropic expansion pattern (flow), which can be described in terms of a Fourier series. The various Fourier components v_n originate from pressure gradients, due to the collision geometry in non-central collisions (typically the quadrupole component v₂, called elliptic flow) or to fluctuations in the initial nucleon density (typically triangular flow v₃ and higher order components). 

Late autumn 2018, the ALICE experiment collected a high-statistics data set with Pb-Pb collisions at a centre-of-mass energy of 5.02 TeV. High-quality reference data from p-p collisions at the same energy are also available.

Open charm mesons, such as the D⁰, have not been measured yet in heavy-ion collisions in the CERN-SPS energy domain. The recent upgrade of the NA61/SHINE experiment will allow this for the first time, adding strong constrains on the searches for the critical point of the phase diagram of nuclear matter.

Heavy nuclei at ultrarelativistic speeds are sources of intense electromagnetic fields which interact with the nuclear collision partner and lead to photoproduction of charm-anticharm quark pairs. The charm photoproduction cross section is sensitive to the gluonic nuclear structure, which depends on initial-state cold nuclear matter effects like gluon saturation.