arXiv Machine Learning By Matthieu Le Lain, Ga\"el Cessateur, S\'ebastien Lef\`evre

Self-Supervised Representation Learning: From Spectral Foundation Models to Auroral Emission Spectra

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The paper presents a self‑supervised approach to learning representations of auroral emission spectra using a 1D Vision Transformer trained with a masked autoencoder on 223,000 unlabelled spectra. The pretrained model recovers key emission‑line intensity ratios with high accuracy (R² = 0.91) and, with a single linear probe, matches expert‑designed feature classifiers. When fine‑tuned, it surpasses the previous supervised auroral classifier (macro‑AP 88.5 vs. 77.8) and achieves a 0.870 mAP, outperforming a model trained from scratch by 0.159 using only 10 % of the labels, while attribution reveals reliance on N₂⁺ bands.

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