Related papers: QCD evolution with longitudinal fields and heavy q…
We investigate transition form factors between non-relativistic QCD bound states at large recoil energy. Assuming the decaying quark to be much heavier than its decay product, the relativistic dynamics can be treated according to the…
We consider interjet observables in hard QCD processes given by the energy flow E_out in a region away from all hard jets. Here the QCD radiation is depleted (E_out << Q), and therefore these observables provide ideal means to study…
As it was suggested by previous works on a modified perturbation expansion for QCD, the possibility for the generation of large quark condensates in the mass-less version of the theory is explored. For this purpose, it is firstly presented…
In this thesis the finite temperature transition between confined and deconfined matter is studied at zero and nonzero quark densities. The findings are relevant for the understanding of the evolution of the early Universe and contemporary…
We present preliminary results of a determination of the semileptonic form factor for the decay of pseudoscalar heavy-light mesons to pseudoscalar light-light mesons in full QCD. In this preliminary study we focus on the effects of…
We review a number of results for the spectrum and inclusive decays of heavy quarkonium systems which can be derived from QCD under well controlled approximations. They essentially follow from the hierarchy of scales in these systems, which…
These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic $B$ decays…
We theoretically study the geometric effect of quantum dynamical evolution in the presence of a nonequilibrium noisy environment. We derive the expression of the time dependent geometric phase in terms of the dynamical evolution and the…
We perform real-time lattice simulations of nonequilibrium quark production in the longitudinally expanding QCD plasma. Starting from a highly occupied gluonic state with vacuum quark sector, we extract the time evolution of quark and gluon…
Fragmentation of heavy quarks into heavy-flavoured hadrons receives both perturbative and non-perturbative contributions. We consider perturbative QCD corrections to heavy quark production in $e^+e^-$ collisions to next-to-next-to-leading…
Recent high-precision measurements of nuclear deep inelastic scattering at high x and moderate 6 < Q$^2$ < 9GeV$^2$ give a rare opportunity to reach the quark distributions in the {\it superfast} region, in which the momentum fraction of…
These lectures stress the theoretical elements that underlie a wide range of phenomenological studies of high-energy QCD, which include both soft and hard processes. After a brief introduction to the basics of QCD, various aspects of…
The bound states of a heavy quark and antiquark ($c\bar{c}, b\bar{b}$) are ideal probes to explore the quark-gluon plasma created in relativistic heavy-ion collisions at the RHIC and LHC. Not only have they become experimentally accessible…
A functional partial differential equation is set for the proper graphs generating functional of QED in external electromagnetic fields. This equation leads to the evolution of the proper graphs with the external field amplitude and the…
Heavy quarks are valuable probes of the electromagnetic field and the initial condition of the quark-gluon plasma (QGP) matter produced in high-energy nuclear collisions. Within an improved Langevin model that is coupled to a…
The early dynamics in heavy-ion collisions involves a rapid, far from equilibrium evolution. This early pre-equilibrium stage of the dynamics can be modeled using kinetic equations. The effect of this pre-equilibrium stage on final…
We discuss recent progress in the study of in-medium heavy quarkonium using first-principles lattice QCD calculations and effective field theory. In particular our focus lies on real-time information carried by QCD spectral functions and we…
In master-field simulations of lattice QCD, the expectation values of interest are obtained from a single or at most a few representative gauge-field configurations on very large lattices. If the light quarks are included, the generation of…
Analysing the asymptotic behaviour of the quark-quark elastic scattering amplitude at high energy and fixed transferred momentum and assuming that gluon is reggeized, we obtain the evolution equation for the gluon Regge trajectory in QCD.…
We review theoretical approaches to form factors that arise in heavy-meson decays and are hadronic expressions of non-perturbative QCD. After motivating their origin in QCD factorisation, we retrace their evolution from quark-model…