Books

This proceeding summarizes recent measurements of the Cabibbo-Kobayashi-Maskawa (CKM)matrix elements |𝑉𝑐𝑏 | and |𝑉𝑢𝑏 | at the Belle and Belle II experiments. It provides insights derivedfrom both exclusive and inclusive determinations. [...]

In this thesis, measurements performed using proton-proton collision data at $\sqrt{s} = 13$TeV collected by the CMS experiment at the CERN LHC, in the years 2016, 2017, and 2018, are presented. The data correspond to an integrated luminosity of 138$~\mathrm{fb}^{-1}$.New results on top quark pair production in association with a photon ($\mathrm{t\bar{t}\gamma}$) are presented. [...]

With the advent of ultrafast optics and controllable waveforms consisting of only a few oscillations of the electric field, the idea of controlling electrons at the frequency of light was born. This established the potential of using a controlled optical waveform to switch electronic circuit elements at the frequency of an optical wave, typically on the order of 0.1 to 1 petahertz(1015 Hz). [...]

Double parton scattering (DPS) describes a process in hadron-hadron scattering in which two partons are extracted from each initial hadron and then initiate hard scattering processes separated by a finite distance. After factorising the hadronic process, one obtains parton distributions functions that characterise the behaviour of partons inside the hadron at non-perturbative scales. [...]

Laser-wakefield acceleration (LWFA) is a promising, emerging technology for future accelerator-based X-ray light sources, which are essential tools in various fields of science, industry and medicine. In laser-wakefield acceleration, an intense laser pulse drives a plasma wave that supports high accelerating field gradients. [...]

The Large Hadron Collider (LHC) will undergo a major “High Luminosity” upgrade with the goal of delivering a peak instantaneous luminosity of 5 − 7.5 × 10^34 cm−2s−1 by 2029. In order for the CMS experiment to cope with the higher radiation levels and data rates, the current CMS Silicon Tracker will be replaced. [...]

A measurement of inclusive jet cross sections in high-Q2 neutral current deep-inelastic scatteringis performed using data collected by the ZEUS detector at the HERA e±p collider. The datawere taken in the years 2004 to 2007 at a centre-of-mass energy of 318 GeV and correspond toan integrated luminosity of 347 pb−1. [...]

In free-electron laser injectors the so-called microbunching instability can severely degrade the beam quality of electron bunches and therefore negatively impact the performance of the free-electron laser. Precise understanding of the microbunching process is required to develop mitigation strategies that minimize the negative impact of the instability.In this work, two approaches of investigating the microbunching instability are presented – one analytical and one numerical. [...]

The new electron-proton collider HERA at DESY has been put into operation in 1992 together with the experiments H1 and ZEUS. With HERA, high energy physics has entered a new territory far beyond the reach of previous lepton-nucleon scattering experiments. [...]

In einer Photogun wird mit einem Laserpuls ein Elektronenpaket aus einer Photokathode herausgelöst, und sofort in einer Kavität auf hohe Energie beschleunigt. Zur Strahlführung dient ein Solenoidmagnet. [...]