Measurement of D Meson Production

This thesis investigates the D meson production as a probe into quark production dynamics and to search for lepton-flavor violations. By analyzing collision data collected by the ATLAS detector at CERN, production of D meson is measured, including in the high-momentum region that has not been studied previously. The differential cross-sections are measured as a function of transverse momentum and pseudorapidity, and compared with next-to-leading-order QCD predictions. The predictions are found to be consistent with the measurements in the visible kinematic region within the large theoretical uncertainties. Additionally, the study explores the implications of these results for enhancing the detection of lepton-flavor-violating tau lepton decays.