The 16 pb^-1 of e^–p data taken with the ZEUS detector during the 1998/99 running period of HERA have been used to measure neutral current single- and double-differential cross sections in deep inelastic ...

Das Experiment MOMO am Cooler Synchrotron COSY im Forschungszentrum Jülich untersucht mittels einer exklusiven Messung die schwellennahe Produktion π von Mesonen anhand der Reaktionen <i>p d -> ³He π⁺ ...

<p>Inclusive cross-sections for the production of open beauty in ep collisions at HERA are measured. The data were recorded with the ZEUS detector between 1996 and 2000. The measurements are restricted to photoproduction ...

<p>An evaluation of the discovery potential for NMSSM Higgs bosons of the ATLAS experiment at the LHC is presented. For this purpose, seven two-dimensional benchmark planes in the six-dimensional parameter space of the ...

So far experimentally not ruled out, the stealthy Higgs scenario proposes a hidden scalar sector, to which only the Higgs has non-vanishing and possibly large couplings. Due to decays into the scalars the Higgs acquires a ...

The measurement of the effective weak mixing angle with the ATLAS experiment at the LHC is presented. It is extracted from the forward--backward asymmetry in the polar angle distribution of the muons originating from $Z$ ...

This thesis describes three machine learning algorithms that can be used for physics analyses. The first is a density estimator that was derived from the Green’s function identity of the Laplace operator and is capable of tagging data samples according to the signal purity. This latter task can also be performed with regression methods, and such an algorithm was implemented based on fast multi-dimensional polynomial regression. The accuracy was improved with a decision tree using smooth boundaries. Both methods apply rigorous checks against overtraining to make sure the results are drawn from statistically significant features. These two methods were applied in the search for the single top-quark production with a W boson. Their separation power differ highly in favour for the regression method, mainly be- cause it can exploit the extra information available during training. The third method is an unsupervised learning algorithm that offers finding an optimal coordinate system for a sample in the sense of maximal information entropy, which may aid future methods to model data....

Beyond the established Standard Model (SM), the search for new physics is among the most important ventures of modern physics. Supersymmetry (SUSY) is a natural candidate for an extension of the SM to account for unexplained ...

In this thesis, the measurement of the inclusive cross section of the production of two b-jets in association with a Z boson is measured where the Z can decay to an electron-positron pair or to a muon-antimuon pair. The ...

In this thesis, a search for the H→b¯b decay mode of the Standard Model Higgs boson in associated production with a vector boson is presented. The search is based on the entire data-set recorded by the ATLAS experiment in ...