本論文利用 LHC Run 3（2022 年）期間在 √s = 13.6 TeV 下收集的質子-質子碰撞數據（積分亮度約為 27.0 fb−1），呈現了 CMS 探測器中電子觸發效率的測量結果。準確的數據與模擬校正對於標準模型的精確測量以及新物理現象的搜尋至關重要。 單電子高階觸發（High-Level Trigger）的效率是利用應用於 Z → ee 事件的 Tag-and-Probe 方法測量的。通過（passing）和未通過（failing）探測電子的不變質量分佈是使用標稱的信號加背景模型同時擬合的，而替代的信號和背景參數化模型則用於評估系統誤差。測量是在電子橫向動量 (pT ) 和贗快度 (η) 的二維區間中進行的。 結果顯示，對於 pT 遠高於觸發閾值的電子，觸發效率在桶部區域達到 96% 至 98%的平原值，在端蓋區域則在 90% 至 92% 之間。數據與模擬之間的殘餘差異已被量化，得出的數據對模擬比例因子（Scale Factors）在大多數運動學相空間中通常在 1 的 5%以內。這些比例因子以及詳細的效率圖和相關誤差，為 Run 3 期間依賴單電子觸發的CMS 分析提供了可靠的校正。;This thesis presents a measurement of the electron trigger efficiencies in the CMS detector using proton–proton collision data collected during LHC Run 3 (2022) at √s=13.6 TeV with an integrated luminosity of ~27.0 〖fb〗^(-1). Accurate data-to-simulation corrections are crucial for precision measurements of the Standard Model and for searches for new physics phenomena. The efficiency of the single-electron High-Level Trigger is measured using the Tag-and-Probe method applied to Z→ee events. The invariant-mass distributions of passing and failing probes are simultaneously fitted using a nominal signal-plus-background model, while alternative signal and background parameterizations are employed to evaluate systematic uncertainties.
The measurement is performed in two-dimensional bins of electron transverse momentum (p_T) and pseudorapidity (η). The results indicate that the trigger efficiency reaches a plateau of between 96% and 98% in the barrel region and between 90% and 92% in the endcaps for electrons with p_T well above the trigger threshold. Residual discrepancies between data and simulation are quantified, yielding data-to-simulation scale factors that are typically found to be within 5% of unity across the majority of the kinematic phase space. These scale factors, along with detailed efficiency maps and associated uncertainties, provide reliable corrections for CMS analyses relying on single-electron triggers during Run 3.
