Speaker
Description
The Timepix3 detector network installed inside the ATLAS cavern [1] has demonstrated reliable performance for measuring particle fluxes and monitoring luminosity during LHC operations [2][4]. As of 2025, the network comprises fourteen operational detectors distributed throughout the ATLAS detector, exposing them to different radiation fields and flux levels. Detectors closer to the interaction point provide high-statistics measurements, while those at greater distance enable cross-validation, systematic uncertainty assessment, and long-term studies of radiation-induced signal degradation.
Each detector operates independently, requiring no external triggers or online information, and the network is fully synchronized with the LHC orbit clock, allowing for bunch-sensitive real time luminosity measurements. Its modular design further allows interventions and manipulation without affecting ATLAS performance, enhancing operational efficiency.
This contribution presents the performance of the Timepix3 network for luminosity measurements during Van der Meer (vdM) scans. The advantages of its design and operational features enabled precise results for the p–O, O–O, and pp scans. Since vdM scans provide the reference for absolute luminosity calibration, these studies show that the Timepix3 network can contribute to absolute luminosity determination. Initial fits to the scan profiles confirm the consistency and reliability of the results.
The results further show how Timepix3 detectors provide detailed analysis of particle signatures, enabling their classification into minimum ionizing particles, highly ionizing particles, gamma rays, neutrons, and electrons, as well as the reconstruction of particle trajectories. These capabilities are used to characterize the radiation environment [3] and to separate the collision peak from the delayed particle tail in each bunch crossing, reducing the overlap of consecutive bunches and improving the signal-to-background ratio [4].
Overall, these results will demonstrate that the Timepix3 detector is a versatile tool for both online and offline beam monitoring. Its highlighted performance shows how it is a strong candidate for luminosity calibration and long-term monitoring in high-luminosity LHC operations, providing an independent and complementary approach to beam monitoring.
[1] P. Burian et al. “Timepix3 detector network at ATLAS experiment” JINST 13 C11024 (2018) \url{https://iopscience.iop.org/article/10.1088/1748-0221/13/11/C11024/meta}
[2] B. Bergmann et al., “Relative luminosity measurement with Timepix3 in ATLAS” JINST 15 C01039 (2020). \url{https://iopscience.iop.org/article/10.1088/1748-0221/15/01/C01039/meta}
[3] B. Bergmann et al., “Characterization of the Radiation Field in the ATLAS Experiment with Timepix Detectors”, in IEEE Transactions on Nuclear Science 66, no. 7, pp. 1861-1869 (2019) \url{https://ieeexplore.ieee.org/abstract/document/8720202}
[4] B. Bergmann et al., “Evaluation of Timepix3 as a luminosity detector at LHC during 2018 pp collisions at \sqrt{s}=13 TeV” Eur. Phys. J. C 85, 904 (2025). \url{https://doi.org/10.1140/epjc/s10052-025-14631-x}
| Position | PhD Student |
|---|---|
| Affiliation | Czech Technical University in Prague (CZ) |
| Country | Czech Republic |