TY  - THES
A3  - Wagner, Wolfgang
AB  - In this dissertation, a measurement of differential production cross sections of single top quarks and top antiquarks produced via the $t$-channel exchange of a virtual $W$-boson is presented. The cross sections are measured as a function of the transverse momentum and absolute rapidity of the top quark and top antiquark. Absolute and normalised differential cross sections are measured as well as the differential ratio between the top-quark and top-antiquark cross sections. The analysed proton-proton collision data was collected by the ATLAS detector at the Large Hadron Collider in the years 2015--2018 at a centre-of-mass energy of 13 TeV and corresponds to an integrated luminosity of 140 fb$^{-1}$. The measured distributions are corrected for detector resolution and acceptance effects. Systematic and statistical uncertainties in the measurement are evaluated. The obtained differential cross sections are compared to theoretical predictions obtained from fixed-order calculations, various parton distribution functions and different event-generator and parton-shower programs. Overall, a good agreement within the measurement uncertainties is observed, where the measurement is limited by systematic uncertainties. The measurement results are interpreted in an effective field theory approach to constrain the Wilson-coefficient $C_{Qq}^{3,1}/\Lambda^2$ associated with a four-quark operator. The operator is found to have a significant impact on the acceptance of signal events, which is evaluated and taken into consideration for the interpretation.
AU  - Stratmann, Maren
CY  - Wuppertal
DA  - 2026
DO  - 10.25926/BUW/0-1079
DP  - Bergische Universität Wuppertal
LA  - eng
N1  - Bergische Universität Wuppertal, Dissertation, 2026
PB  - Bergische Universität Wuppertal
SP  - 1 Online-Ressource (VII, 208 Seiten)
T2  - Physik
TI  - Measurement of the differential single-top-quark t-channel production cross section at √s = 13 TeV with the ATLAS detector
UR  - https://nbn-resolving.org/urn:nbn:de:hbz:468-2-7650
Y2  - 2026-11-01T02:20:04
ER  -