arXiv subjects

Patryk Kubiczek

Publications and source records attributed to Patryk Kubiczek.

3 recordsLinked to original sources

arXiv2019

Exact real-time dynamics of single-impurity Anderson model from a single-spin hybridization-expansion

In this work we introduce a modified real-time continuous-time hybridization-expansion quantum Monte Carlo solver for a time-dependent single-orbital Anderson impurity model: CT-1/2-HYB-QMC. In the proposed method the diagrammatic expansion is performed only for one out of the two spin channels, while the resulting effective single-particle problem for the other spin is solved semi-analytically for each expansion diagram. CT-1/2-HYB-QMC alleviates the dynamical sign problem by reducing the order of sampled diagrams and makes it possible to reach twice as long time scales in comparison to the standard CT-HYB method. We illustrate the new solver by calculating an electric current through impurity in paramagnetic and spin-polarized cases.

cond-mat.str-el↗

arXiv2016

Proton structure in high-energy high-multiplicity p-p collisions

A few-body proton image, expected to be derivable from QCD in the renormalization group procedure for effective particles, is used within the Monte Carlo Glauber model to calculate the anisotropy coefficients in the initial collision-state of matter in high-energy high-multiplicity proton-proton interaction events. We estimate the ridge-like correlations in the final hadronic state by assuming their proportionality to the initial collision-state anisotropy. In our estimates, some distinct few-body proton structures appear capable of accounting for the magnitude of p-p ridge effect, with potentially discernible differences in dependence on multiplicity.

hep-ph↗

arXiv2015

Manifestation of proton structure in the initial-state anisotropies in high-energy proton-proton collisions

Ridge-like correlations in high-energy proton-proton collisions reported by the CMS collaboration suggest a collective flow that resembles the one in heavy-ion collisions. If the hydrodynamic description is valid then the effect results from the initial anisotropy of the colliding matter which depends on the structure of protons. Following recent theoretical developments, we propose several phenomenological models of the proton structure and calculate the anisotropy coefficients using the Monte Carlo Glauber model. Our estimates suggest that the event multiplicity dependence allows one to discriminate between different proton models.

hep-ph↗