SAIP2026

Enhancing Forward Jet Reconstruction with HGTD Timing in the ATLAS Particle Flow Algorithm

9 Jul 2026, 09:50

20m

Lecture Hall GH3 (University of the Western Cape)

Oral Presentation Track B - Nuclear, Particle and Radiation Physics Nuclear, Particle and Radiation Physics -2

Speaker

Thabo James Lepota (University of the Witwatersrand)

Description

The High Granularity Timing Detector (HGTD) in the ATLAS experiment is designed to provide precision timing measurements for charged particle tracks in the forward region, enabling enhanced pileup mitigation at the High-Luminosity Large Hadron Collider (HL-LHC). In this study, we investigate the integration of HGTD timing information into the Charged Hadron Subtraction (CHS) procedure within the ATLAS Particle Flow (PFlow) algorithm. By combining per-track timing with primary vertex time reconstruction, timing-based consistency criteria are developed to discriminate between hard-scatter and pileup tracks. The performance of these selections is evaluated using simulated proton–proton collision events, with particular focus on their impact on jet reconstruction in the forward region. Key observables include jet reconstruction efficiency, jet energy resolution, and residual pileup contamination. Comparisons are made between the baseline CHS approach and timing-augmented configurations to quantify performance gains under high pileup conditions expected at the HL-LHC. The results demonstrate the extent to which precision timing can improve pileup suppression while preserving jet performance. An optimal set of timing selection criteria is identified and proposed for integration into the Run 4 ATLAS PFlow reconstruction framework. This work contributes to the ongoing validation and optimisation of HGTD-driven reconstruction strategies and supports future physics analyses in high-density collision environments.