HEPTv2: End-to-End Efficient Point Transformer for Charged Particle Reconstruction
Summary
HEPTv2 is an end-to-end point-transformer architecture designed for charged-particle tracking, a fundamental high-energy-physics inference problem at the High-Luminosity Large Hadron Collider (HL-LHC). This system reconstructs trajectories from sparse detector measurements in one trainable pipeline, eliminating the need for auxiliary stages like graph construction, clustering, or filtering. HEPTv2 integrates a locality-aware point encoder, which uses locality-sensitive hashing for efficient local attention, with a track decoder that predicts complete trajectories via sectorized decoding and direct hit-to-track prediction. The full pipeline is optimized end-to-end under joint encoder-decoder supervision. On the TrackML dataset, HEPTv2 achieves 98.6% double-majority tracking efficiency and a 0.8% fake rate. It requires approximately 15 ms inference time and 0.4 GB peak memory per event on an NVIDIA A100 GPU, scaling linearly for events up to 5×10^5 hits. This architecture improves efficiency by 4.5% over previous transformers and 1.1-2.2% over optimized graph-based pipelines, while reducing latency by factors of 7 and 38-52.
Key takeaway
For Machine Learning Engineers developing particle reconstruction systems for high-luminosity colliders, HEPTv2 demonstrates that end-to-end point transformers can significantly outperform traditional graph-based or multi-stage transformer approaches. You should evaluate integrating similar end-to-end architectures, leveraging locality-aware encoding and direct hit-to-track prediction, to achieve superior accuracy and drastically reduced latency. This approach is crucial for meeting the real-time processing demands of future experiments like the HL-LHC.
Key insights
HEPTv2 is an end-to-end point transformer for charged particle reconstruction, achieving high accuracy and efficiency without graph processing.
Principles
- Locality-sensitive hashing preserves tracking-relevant geometry for efficient local attention.
- End-to-end optimization improves efficiency and accuracy in complex reconstruction tasks.
- Sectorized decoding and direct hit-to-track prediction resolve combinatorial ambiguities.
Method
HEPTv2 combines a locality-aware point encoder using locality-sensitive hashing with a track decoder that predicts trajectories via sectorized decoding and direct hit-to-track prediction, optimized end-to-end.
In practice
- Real-time particle reconstruction at HL-LHC.
- Efficient processing of high-density collision data.
Topics
- Charged Particle Reconstruction
- Point Transformers
- High Energy Physics
- Locality-Sensitive Hashing
- HL-LHC
- Inference Efficiency
Best for: AI Scientist, Research Scientist, Machine Learning Engineer
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Editorial summary, takeaway, and curation by AIssential. Original article published by Machine Learning.