Enhancing low energy reconstruction and classification in KM3NeT/ORCA with transformers
Iván Mozún Mateo
TL;DR
This paper tackles the reconstruction of low-energy neutrino events in KM3NeT/ORCA by introducing a transformer model augmented with physics- and detector-informed attention masks. By encoding domain constraints in the attention mechanism, the approach improves direction and energy reconstruction at low energies compared to traditional maximum-likelihood fits and enables effective transfer learning across telescope configurations. The results show notable gains in AUROC with limited training data when leveraging pretraining on larger configurations, highlighting both improved performance and data efficiency for a detector still under construction. The proposed method offers practical benefits for neutrino oscillation studies and demonstrates how deep learning models can integrate physical knowledge to exploit the full potential of complex neutrino telescope data.
Abstract
The current KM3NeT/ORCA neutrino telescope, still under construction, has not yet reached its full potential in neutrino reconstruction capability. When training any deep learning model, no explicit information about the physics or the detector is provided, thus they remain unknown to the model. This study leverages the strengths of transformers by incorporating attention masks inspired by the physics and detector design, making the model understand both the telescope design and the neutrino physics measured on it. The study also shows the efficacy of transformers on retaining valuable information between detectors when doing fine-tuning from one configurations to another.
