Speaker
Dr
Alexander Rothkopf
(Institute for Theoretical Physics, Heidelberg University)
Description
Heavy quarkonium, the bound states of a heavy quark and antiquark have become precision observables in heavy-ion collisions at RHIC and LHC over the past few years. Understanding their dynamical behavior when immersed in a medium will allow us to extract the properties of the strongly coupled quark-gluon plasma created in the collision center. Lattice QCD is ideally suited for this task, as it can provide non-perturbative insight into the QCD medium in the phenomenologically relevant region around the phase transition. The challenge of extracting real-time information from Euclidean lattice simulations is answered through improved Bayesian reconstructions [1] of spectral functions.
For static quark-antiquark pairs, effective field theory methods allow us to derive a Schroedinger equation to describe their time evolution. The real- and imaginary part of the in-medium potential that summarizes the interaction between quarkonium and the surrounding QGP is extracted from spectral functions of lattice QCD Wilson line correlators [2].
Quarkonia of finite mass can also be directly simulated using a lattice discretized version of the effective field theory NRQCD. Evaluated on current generation full QCD ensembles of the HotQCD collaboration, we find from reconstructed meson spectral functions that both the Upsilon as well as the \chi_b ground state survive well into the QGP phase up to T=249MeV [3].
[1] Y.Burnier, A.R. Phys.Rev.Lett. 111 (2013) 182003
[2] Y.Burnier, O. Kaczmarek and A.R. arXiv:1410.2546 t.b.p. in PRL
[3] S. Kim, P. Petreczky and A.R. arXiv:1409.3630 t.b.p. in PRD
Primary author
Dr
Alexander Rothkopf
(Institute for Theoretical Physics, Heidelberg University)
