arXiv subjects

R. Straka

Publications and source records attributed to R. Straka.

4 recordsLinked to original sources

arXiv2021

Influence of scattering versus coherent parton branching on the $k_T$ broadening of QCD cascades in a medium

We studied the evolution of jets within a medium that contains both, transverse kicks as well as medium induced coherent radiation. In this framework parton branching occurs simultaneously to scatterings within the medium, leading to the interference effects that reproduce the well known BDMPS-Z emission rates and sizeable transverse momentum broadening. We examined the relative importances of transverse momentum broadening from the coherent splittings and different types of in-medium scatterings and found a clear hierarchy of the influences from different scattering effects and deflections during branchings.

hep-ph↗

arXiv2021

Effects of transverse momentum broadening of parton cascades from coherent emissions and scatterings in a medium

Highly energetic particles in the medium of a quark gluon plasma undergo processes of coherent medium induced radiation and scatterings off medium particles. We solved the evolution equations for particle fragmentation functions that describe in-medium evolution via these two in-medium processes numerically via Monte-Carlo algorithms. We study the in-medium broadening of the distribution over momentum components transverse to the jet-axis for different cases of jet-medium interactions and different values of average transverse momentum transfer.

hep-ph↗

arXiv2020

Medium induced QCD cascades: broadening and rescattering during branching

We study evolution equations describing jet propagation through quark--gluon plasma (QGP). In particular we investigate the contribution of momentum transfer during branching and find that such a contribution is sizeable. Furthermore, we study various approximations, such as the Gaussian approximation and the diffusive approximation to the jet-broadening term. We notice that in order to reproduce the BDIM equation (without the momentum transfer in the branching) the diffusive approximation requires a very large value of the jet-quenching parameter $\hat q$.

hep-ph↗

arXiv2019

Solutions of evolution equations for medium-induced QCD cascades

In this paper we present solutions of evolution equations for inclusive distribution of gluons as produced by jet traversing quark-gluon plasma. We reformulate the original equations in such a form that the virtual and unresolved-real emissions as well as unresolved collisions with medium are resummed in a Sudakov-type form factor. The resulting integral equations are then solved most efficiently with use of newly developed Markov Chain Monte Carlo algorithms implemented in a dedicated program called MINCAS. Their results for a gluon energy density are compared with an analytical solution and a differential numerical method. Some results for gluon transverse-momentum distributions are also presented. They exhibit interesting patterns not discussed so far in the literature, in particular a departure from the Gaussian behaviour - which does not happen in approximate analytical solutions.

hep-ph↗