Henry Day-Hall

About

I am a computational particle physicist specializing in generative simulation and jet physics. My research bridges algorithmic innovation, including the development of novel jet definition techniques leveraging eigenvalue spectra. I have contributed to critical infrastructure of the ATLAS experiment, such as jet energy spectrum and resolution calibration, and the validation and deployment of fast simulation frameworks. Currently, my work focuses on pioneering fast generative methods for next-generation Higgs factory calorimeters and modeling extensive air showers, with an emphasis on scalability and computational efficiency.

Find my github at github.com/HenryDayHall. In particular, please check out;

• My contributions to CaloClouds3 (2025) github.com/FLC-QU-hep/CaloClouds-3. If you are a member of a HelmHoltz institute, you can try it out in the Helmholtz Model Zoo at hmz-hub.desy.de.
• Physics-playground, an outreach project based on Tensorflow's playground (2024) github.com/HenryDayHall/playground. You can try it out at physics-playground.day-hall.eu.
• A python library to implement Step (2022) github.com/HenryDayHall/step.

Publications

• AllShowers: One model for all calorimeter showers (2026) arXiv:2601.11716
• A First Full Physics Benchmark for Highly Granular Calorimeter Surrogates (2025) arXiv:2511.17293
• CaloClouds3: A First Full Physics Benchmark for Highly Granular Calorimeter Surrogates (2025) arXiv:2511.01460
• Software and computing for Run 3 of the ATLAS experiment at the LHC (2025) doi.org/10.1140/epjc/s10052-024-13701-w Specific contribution; Validation of AtlFast3
• Measurements of jet cross-section ratios in 13 TeV proton-proton collisions with ATLAS (2024) doi.org/10.1103/PhysRevD.110.072019 Specific contribution; Columnar analysis development for total jet cross sections
• Fat b-Jet Analyses Using Old and New Clustering Algorithms in New Higgs Boson Searches at the LHC (2023) arXiv:2303.05189
• Spectral clustering for jet reconstruction (2022) doi.org/10.22323/1.414.0771
• Revisiting Jet Clustering Algorithms for New Higgs Boson Searches in Hadronic Final States (2022) arXiv:2008.02499
• Spectral Clustering for Jet Physics (2022) arXiv:2104.01972
• Mapping pp → A → ZH → l+l−bƃ and pp → H → ZA → l+l−bƃ Current and Future Searches onto 2HDM Parameter Spaces (2021) arXiv:2006.05177
• Extracting jet signals of New Higgs Physics: from traditional analysis to machine learning (2021) eprints.soton.ac.uk/473633/