arXiv Machine Learning By Agastya Gaur (University of Illinois Urbana-Champaign, SETI Institute), Cristina M. Dalle Ore (Carl Sagan Center, SETI Institute), Alessandra Ricca (NASA Ames Research Center, NASA Ames Research Center)

TNFlow: Amortized Posterior Inference for Trans-Neptunian Object Surface Composition

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TNFlow is a transformer‑based normalizing flow model designed to infer the surface composition of Trans‑Neptunian Objects (TNOs) from their reflectance spectra. It is trained on synthetic spectra generated by the Shkuratov radiative transfer model and can invert a spectrum in about 0.7 s on a single CPU core, producing a multimodal posterior over simplex‑valid compositions and grain sizes. On synthetic data, the model’s highest‑weight mode achieves a mean total‑variation distance of 0.149 from ground truth, and it generalizes well to unseen component combinations, though qualitative tests on real JWST spectra reveal potential biases linked to simulator fidelity or training data.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Machine Learning.

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