OpenAccess

This thesis presents two research works carried out within the Compact Muon Solenoid (CMS) experiment at the CERN Large Hadron Collider (LHC): the system validation of the scintillator section of the High Granularity Calorimeter (HGCAL), and a search for a heavy resonance coupling to top quarks and produced in association with top quark pairs in proton–proton collisions at center-of-mass energies of 13 and 13.6 TeV. For the High-Luminosity LHC (HL-LHC) phase, the endcap calorimeters of CMS will be replaced by the HGCAL, a high-precision sampling calorimeter designed to cope with the extreme radiation and pileup conditions expected at the HL-LHC. [...]

The discrepancy in the attosecond time delay between theory and experiment near the 3⁢𝑠 Cooper minimum (CM) of Ar is addressed. It is found that inclusion of the relaxation effects in the time delay difference between Ar 3⁢𝑠 and 3⁢𝑝 photoionization near the 3⁢𝑠 CM dramatically alters the 3⁢𝑠 time delay and brings the theory into substantial agreement with experiment using the relativistic-random-phase approximation with relaxation. [...]

Wood tracheids and fibers exhibit diverse structures and shapes across plant species. The hierarchical structure and composition of cellulose, hemicelluloses, and lignin enables wood to withstand high stress [...]

Metal additive manufacturing is a promising route for producing complex, highly customized embeddedstructures for nuclear fusion environments, such as breeding blankets and divertors. These applicationsrequire steels with high thermomechanical stability and resistance to irradiation, yet AM processing oftenleads to undesired microstructural heterogeneities, including the formation of metastable phases. [...]

This study explores the use of acoustic emission (AE) signals for in situ characterization of recrystallization during laser processing. With millisecond-scale temporal resolution, AE monitoring can detect critical events during the recrystallization processes, including dislocation reorganization, nucleation, and grain growth. [...]

We present the design and characterization of a fully automated free-standing liquid crystal (FSLC) film holder, enabling remote and precise control of liquid crystal (LC) volume release, wiping speed, and temperature. Using 4-octyl-4′-cyanobiphenyl (8CB) as a test material, we systematically investigated the influence of formation parameters on the resulting film thickness and temporal evolution [...]

1,2-Bis(trihalogenosilyl)benzenes are versatile synthetic building blocks and represent a unique class of ditopic Lewis acids. Building on the recently reported compound 1,2-(Cl3Si)2C6H2Me2 (1Cl; Me groups in 4,5-positions), the practical synthetic access to its sixfold fluorinated (1F), brominated (1Br), and iodinated (1I) congeners is disclosed. [...]

Powder aerosol deposition (PAD or ADM) is a coating technique to produce ceramic films at room temperature. Although the deposition mechanism has been clarified in some respects, unanswered questions remain. [...]

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H $\to$$\mathrm{c\bar{c}}$, produced in association with a top quark-antiquark pair ($\mathrm{t\bar{t}}$H) is presented. The search is performed with data from proton-proton collisions at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. [...]

A general search is presented for supersymmetric particles (sparticles) in scenarios featuring compressed mass spectra using proton-proton collisions at a center-of-mass energy of 13 TeV, recorded with the CMS detector at the LHC. The analyzed data sample corresponds to an integrated luminosity of 138 fb$^{-1}$. [...]