Diese Arbeit stellt eine Messung des W+W- Produktionswirkungsquerschnitts in pp Kollisionen bei einer Schwerpunktenergie von √s = 13 TeV vor. Der verwendete Datensatz wurde mit dem ATLAS Detektor im Jahr 2015 aufgezeichnet und entspricht einer integrierten Luminosität von 3,16 fb-1. Die W+W- Ereignisse werden über leptonische Zerfälle der W-Bosonen selektiert, wobei jeweils eines der W Bosonen in ein Elektron und ein Elektronneutrino und das andere in ein Myon und ein Myonneutrino zerfällt. Der gemessene Wirkungsquerschnitt in einem Referenzphasenraum, der nahe der Detektorakzeptanz definiert ist, beträgt σ (fiducial, W+W-) = 529 ± 20 (stat.) ± 50 (syst.) ± 11 (lumi.) fb. Das Ergebnis stimmt innerhalb der Fehlergrenzen mit der besten verfügbaren Standardmodell-Vorhersage von 478 ± 17 fb überein. Die kinematischen Verteilungen der im Zerfall der beiden W Bosonen produzierten Leptonen wurden genauer untersucht, um die drei- Eichbosonenkopplung bei den WWγ und WWZ Vertizes zu messen. Abweichungen dieser Kopplungen vom Standardmodell können ein Hinweis auf neue Physik sein. Für die Größen, welche diese anomalen Kopplungen parametrisieren, wurden Konfidenzintervalle berechnet. Die beobachteten Kopplungen stimmen mit dem Standardmodell überein. / This thesis presents a measurement of W+W- production cross section with the pp collision data collected at the ATLAS detector in the year of 2015. The dataset corresponds to a centre-of-mass collision energy of √s = 13 TeV with a total integrated luminosity of 3.16 fb-1. The W+W- signal events are selected using a signature where one of the W bosons decays into an electron and an electron neutrino while the other produces a muon with an associated muon neutrino. The measured cross section in the chosen fiducial phase space close to detector acceptance is σ (fiducial, W+W-) = 529 ± 20 (stat.) ± 50 (syst.) ± 11 (lumi.) fb. The result within the assigned uncertainties is compatible with the best available Standard Model prediction of 478 ± 17 fb. The observed kinematic spectrums of the produced leptons from the decay of the two W bosons are further investigated to study the triple gauge boson couplings at the WWγ und WWZ vertices. The deviation of these couplings from the Standard Model can probe the existence of new physics. The confidence intervals have been calculated for the parameters representing these anomalous couplings. The observations are consistent with the Standard Model expectations.

The way in which macroscopic transport results from microscopic dynamics is one of the important questions in statistical physics. Dynamical systems theory play a key role in a resent advance in this direction. Offering relatively simple models which are easy to study, dynamical systems theory became a standard branch of modern nonequilibrium statistical physics. In the present work the deterministic diffusion generated by simple dynamical systems is considered. The deterministic nature of these systems is more clearly expressed through the dependencies of the transport quantities as functions of systems parameters. For fully hyperbolic dynamical systems these dependencies were found to be highly irregular and, in fact, fractal. The main focus in this work is on nonhyperbolic and on intermittent dynamical systems. First, the climbing sine map is considered which is a nonhyperbolic system with many physical applications. Then we treat anomalous dynamics generated by a paradigmatic subdiffusive map. In both cases these systems display deterministic transport which, under variation of control parameters, is fractal. For both systems we give an explanation of the observed phenomena. The third part of the thesis is devoted to the relation between chaotic and transport properties of dynamical systems. This question lies at the heart of dynamical systems theory. For closed hyperbolic dynamical systems the Pesin theorem links the sum of positive Lyapunov exponents to the Kolmogorov-Sinai entropy. For open hyperbolic systems the escape rate formula is valid. In this work we have formulated generalizations of these formulas for a class of intermittent dynamical systems where the chaotic properties are weaker.

The way in which macroscopic transport results from microscopic dynamics is one of the important questions in statistical physics. Dynamical systems theory play a key role in a resent advance in this direction. Offering relatively simple models which are easy to study, dynamical systems theory became a standard branch of modern nonequilibrium statistical physics. In the present work the deterministic diffusion generated by simple dynamical systems is considered. The deterministic nature of these systems is more clearly expressed through the dependencies of the transport quantities as functions of systems parameters. For fully hyperbolic dynamical systems these dependencies were found to be highly irregular and, in fact, fractal. The main focus in this work is on nonhyperbolic and on intermittent dynamical systems. First, the climbing sine map is considered which is a nonhyperbolic system with many physical applications. Then we treat anomalous dynamics generated by a paradigmatic subdiffusive map. In both cases these systems display deterministic transport which, under variation of control parameters, is fractal. For both systems we give an explanation of the observed phenomena. The third part of the thesis is devoted to the relation between chaotic and transport properties of dynamical systems. This question lies at the heart of dynamical systems theory. For closed hyperbolic dynamical systems the Pesin theorem links the sum of positive Lyapunov exponents to the Kolmogorov-Sinai entropy. For open hyperbolic systems the escape rate formula is valid. In this work we have formulated generalizations of these formulas for a class of intermittent dynamical systems where the chaotic properties are weaker.