deep-REMAP: Probabilistic Parameterization of Stellar Spectra Using Regularized Multi-Task Learning
- URL: http://arxiv.org/abs/2510.09362v1
- Date: Fri, 10 Oct 2025 13:20:06 GMT
- Title: deep-REMAP: Probabilistic Parameterization of Stellar Spectra Using Regularized Multi-Task Learning
- Authors: Sankalp Gilda,
- Abstract summary: deep-REMAP is a novel deep learning framework that utilizes a regularized, multi-task approach to predict stellar atmospheric parameters from observed spectra.<n>We train a deep convolutional neural network on the PHOENIX synthetic spectral library and use transfer learning to fine-tune the model on a small subset of observed FGK dwarf spectra.<n>Deep-REMAP accurately recovers the effective temperature ($T_rmeff$), surface gravity ($log rmg$), and metallicity ([Fe/H]), achieving a precision of, for instance, approximately 75 K in $T
- Score: 0.0
- License: http://creativecommons.org/licenses/by-nc-nd/4.0/
- Abstract: In the era of exploding survey volumes, traditional methods of spectroscopic analysis are being pushed to their limits. In response, we develop deep-REMAP, a novel deep learning framework that utilizes a regularized, multi-task approach to predict stellar atmospheric parameters from observed spectra. We train a deep convolutional neural network on the PHOENIX synthetic spectral library and use transfer learning to fine-tune the model on a small subset of observed FGK dwarf spectra from the MARVELS survey. We then apply the model to 732 uncharacterized FGK giant candidates from the same survey. When validated on 30 MARVELS calibration stars, deep-REMAP accurately recovers the effective temperature ($T_{\rm{eff}}$), surface gravity ($\log \rm{g}$), and metallicity ([Fe/H]), achieving a precision of, for instance, approximately 75 K in $T_{\rm{eff}}$. By combining an asymmetric loss function with an embedding loss, our regression-as-classification framework is interpretable, robust to parameter imbalances, and capable of capturing non-Gaussian uncertainties. While developed for MARVELS, the deep-REMAP framework is extensible to other surveys and synthetic libraries, demonstrating a powerful and automated pathway for stellar characterization.
Related papers
- The Sim-to-Real Gap in MRS Quantification: A Systematic Deep Learning Validation for GABA [0.0]
Quantifying low-concentration metabolites such as GABA is challenging due to low signal-to-noise ratio (SNR) and spectral overlap.<n>We investigate and validate deep learning for complex, low-SNR, overlapping signals from MEGA-PRESS spectra.<n>We select the best models via Bayesian optimisation on 10,000 simulated spectra from slice-profile-aware MEGA-PRESS simulations.
arXiv Detail & Related papers (2026-02-23T19:16:03Z) - GTS: Inference-Time Scaling of Latent Reasoning with a Learnable Gaussian Thought Sampler [54.10960908347221]
We model latent thought exploration as conditional sampling from learnable densities and instantiate this idea as a Gaussian Thought Sampler (GTS)<n>GTS predicts context-dependent perturbation distributions over continuous reasoning states and is trained with GRPO-style policy optimization while keeping the backbone frozen.
arXiv Detail & Related papers (2026-02-15T09:57:47Z) - Spectral Gating Networks [65.9496901693099]
We introduce Spectral Gating Networks (SGN) to introduce frequency-rich expressivity in feed-forward networks.<n>SGN augments a standard activation pathway with a compact spectral pathway and learnable gates that allow the model to start from a stable base behavior.<n>It consistently improves accuracy-efficiency trade-offs under comparable computational budgets.
arXiv Detail & Related papers (2026-02-07T20:00:49Z) - SIGMA: Scalable Spectral Insights for LLM Collapse [51.863164847253366]
We introduce SIGMA (Spectral Inequalities for Gram Matrix Analysis), a unified framework for model collapse.<n>By utilizing benchmarks that deriving and deterministic bounds on the matrix's spectrum, SIGMA provides a mathematically grounded metric to track the contraction of the representation space.<n>We demonstrate that SIGMA effectively captures the transition towards states, offering both theoretical insights into the mechanics of collapse.
arXiv Detail & Related papers (2026-01-06T19:47:11Z) - Classifying Cool Dwarfs: Comprehensive Spectral Typing of Field and Peculiar Dwarfs Using Machine Learning [0.0]
classification of low-mass stars and brown dwarfs.<n>Recent advances in machine learning (ML) methods offer automated approaches for spectral typing.<n>We investigate the application of ML in spectral type classification on low-resolution near-infrared spectra of M0--T9 dwarfs.
arXiv Detail & Related papers (2025-08-12T21:58:55Z) - Inference-Time Scaling of Diffusion Language Models with Particle Gibbs Sampling [70.8832906871441]
We study how to steer generation toward desired rewards without retraining the models.<n>Prior methods typically resample or filter within a single denoising trajectory, optimizing rewards step-by-step without trajectory-level refinement.<n>We introduce particle Gibbs sampling for diffusion language models (PG-DLM), a novel inference-time algorithm enabling trajectory-level refinement while preserving generation perplexity.
arXiv Detail & Related papers (2025-07-11T08:00:47Z) - REAL Sampling: Boosting Factuality and Diversity of Open-Ended Generation via Asymptotic Entropy [93.8400683020273]
Decoding methods for large language models (LLMs) usually struggle with the tradeoff between ensuring factuality and maintaining diversity.
We propose REAL sampling, a decoding method that improved factuality and diversity over nucleus sampling.
arXiv Detail & Related papers (2024-06-11T21:44:49Z) - Using autoencoders and deep transfer learning to determine the stellar parameters of 286 CARMENES M dwarfs [0.0]
We propose a feature-based deep transfer learning (DTL) approach based on autoencoders to determine stellar parameters from high-resolution spectra.
We provide new estimations for the effective temperature, surface gravity, metallicity, and projected rotational velocity for 286 M dwarfs observed by the CARMENES survey.
arXiv Detail & Related papers (2024-05-14T15:42:27Z) - Data-free Weight Compress and Denoise for Large Language Models [96.68582094536032]
We propose a novel approach termed Data-free Joint Rank-k Approximation for compressing the parameter matrices.<n>We achieve a model pruning of 80% parameters while retaining 93.43% of the original performance without any calibration data.
arXiv Detail & Related papers (2024-02-26T05:51:47Z) - deep-REMAP: Parameterization of Stellar Spectra Using Regularized
Multi-Task Learning [0.0]
Deep-Regularized Ensemble-based Multi-task Learning with Asymmetric Loss for Probabilistic Inference ($rmdeep-REMAP$)
We develop a novel framework that utilizes the rich synthetic spectra from the PHOENIX library and observational data from the MARVELS survey to accurately predict stellar atmospheric parameters.
arXiv Detail & Related papers (2023-11-07T05:41:48Z) - Model-Based Reparameterization Policy Gradient Methods: Theory and
Practical Algorithms [88.74308282658133]
Reization (RP) Policy Gradient Methods (PGMs) have been widely adopted for continuous control tasks in robotics and computer graphics.
Recent studies have revealed that, when applied to long-term reinforcement learning problems, model-based RP PGMs may experience chaotic and non-smooth optimization landscapes.
We propose a spectral normalization method to mitigate the exploding variance issue caused by long model unrolls.
arXiv Detail & Related papers (2023-10-30T18:43:21Z) - Local primordial non-Gaussianity from the large-scale clustering of photometric DESI luminous red galaxies [5.534428269834764]
We use angular clustering of luminous red galaxies from the Dark Energy Spectroscopic Instrument (DESI) imaging surveys to constrain the local primordial non-Gaussianity parameter $fnl$.
Our sample comprises over 12 million targets, covering 14,000 square degrees of the sky, with redshifts in the range 0.2 z 1.35$.
We identify Galactic extinction, survey depth, and astronomical seeing as the primary sources of systematic error, and employ linear regression and artificial neural networks to alleviate non-cosmological excess clustering on large scales.
arXiv Detail & Related papers (2023-07-04T14:49:23Z) - Estimation of stellar atmospheric parameters from LAMOST DR8
low-resolution spectra with 20$\leq$SNR$<$30 [2.514059405625551]
This work studied the ($T_texttteff, logg$, [Fe/H] estimation problem for LAMOST DR8 low-resolution spectra with 20$leq$SNR$$30.
Experiments show that the Mean Absolute Errors (MAE) of $T_texttteff, logg$, [Fe/H] are reduced from the LASP (137.6 K, 0.195 dex, 0.091 dex) to LASSO-MLP (84.32 K, 0.137 dex,
arXiv Detail & Related papers (2022-04-13T11:09:24Z) - Inverting brain grey matter models with likelihood-free inference: a
tool for trustable cytoarchitecture measurements [62.997667081978825]
characterisation of the brain grey matter cytoarchitecture with quantitative sensitivity to soma density and volume remains an unsolved challenge in dMRI.
We propose a new forward model, specifically a new system of equations, requiring a few relatively sparse b-shells.
We then apply modern tools from Bayesian analysis known as likelihood-free inference (LFI) to invert our proposed model.
arXiv Detail & Related papers (2021-11-15T09:08:27Z) - Shaping Deep Feature Space towards Gaussian Mixture for Visual
Classification [74.48695037007306]
We propose a Gaussian mixture (GM) loss function for deep neural networks for visual classification.
With a classification margin and a likelihood regularization, the GM loss facilitates both high classification performance and accurate modeling of the feature distribution.
The proposed model can be implemented easily and efficiently without using extra trainable parameters.
arXiv Detail & Related papers (2020-11-18T03:32:27Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.