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Related papers: Improved Lyman Alpha Tomography using Optimized Re…

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The Lyman-alpha forest is a unique probe of large-scale matter density fluctuations at high redshift (z > 2). It is possible to obtain 3D maps of the matter distribution from Lyman-alpha data, using tomographic reconstruction methods. Here,…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 Corentin Ravoux

One of the major science goals over the coming decade is to test fundamental physics with probes of the cosmic large-scale structure out to high redshift. Here we present a fully Bayesian approach to infer the three-dimensional cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Natalia Porqueres , Jens Jasche , Guilhem Lavaux , Torsten Enßlin

Pre-trained vision foundation models (VFMs) provide strong semantic representations, yet their patch-level features are inherently coarse, limiting their effectiveness on tasks requiring fine-grained localization, dense prediction, and…

Computer Vision and Pattern Recognition · Computer Science 2026-05-21 Wentong Li , Zhiyuan Qi , Zichen Zhao , Kai Zhang , Lei Zhang

We present composite spectra constructed from a sample of 242,150 Lyman-alpha (Lya) forest absorbers at redshifts 2.4<z<3.1 identified in quasar spectra from the Baryon Oscillation Spectroscopic Survey (BOSS) as part of Data Release 9 of…

We describe techniques concerning wavelength calibration and sky subtraction to maximise the scientific utility of data from tunable filter instruments. While we specifically address data from the Optical System for Imaging and low…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Tim Weinzirl , Alfonso Aragon-Salamanca , Steven P. Bamford , Bruno Rodriguez del Pino , Meghan E. Gray , Ana L. Chies-Santos

The properties of the Lyman-$\alpha$ absorptions observed in the spectra of QSOs are reviewed: the distribution of column densities and Doppler widths, the redshift evolution, the ``inverse effect'', the clustering. By interpreting the…

Astrophysics · Physics 2007-05-23 S. Cristiani

This paper proposes a novel approach to improve the training efficiency and the generalization performance of Feed Forward Neural Networks (FFNNs) resorting to an optimal rescaling of input features (OFR) carried out by a Genetic Algorithm…

Machine Learning · Computer Science 2024-02-21 Federico Maria Vitrò , Marco Leonesio , Lorenzo Fagiano

(Abridged) Weak gravitational lensing is an ideal probe of the dark universe. In recent years, several linear methods have been developed to reconstruct the density distribution in the Universe in three dimensions, making use of photometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Adrienne Leonard , François-Xavier Dupé , Jean-Luc Starck

Adaptive filter in complex scenarios demands algorithms that integrate fast convergence, low complexity, and robust performance under diverse noise conditions. To address this challenge, we propose a online censoring robust total…

Signal Processing · Electrical Eng. & Systems 2026-05-19 Yi Peng , Haiquan Zhao , Jinhui Hu

High-angular-resolution imaging is crucial for many applications in modern astronomy and astrophysics. The fundamental diffraction limit constrains the resolving power of both ground-based and spaceborne telescopes. The recent idea of a…

Instrumentation and Methods for Astrophysics · Physics 2018-03-12 A. R. Kurek , A. Stachowski , K. Banaszek , A. Pollo

Real-world image restoration is challenging due to complex and interacting mixed degradations. Recent agent-based approaches address this problem by composing multiple task-specific restoration tools. However, empirical analysis reveals…

Computer Vision and Pattern Recognition · Computer Science 2026-05-22 Feng Zhu , Shuyang Xie , Yihan Zeng , Ming Liu , Wangmeng Zuo

The Lyman-alpha forest has opened a new redshift regime for cosmological investigation. At z > 2 it provides a unique probe of cosmic geometry and an independent constraint on dark energy that is not subject to standard candle or ruler…

Astrophysics · Physics 2009-11-13 Andrew R. Marble , Kristoffer A. Eriksen , Chris D. Impey , Lei Bai , Lance Miller

We present new cosmological parameter constraints from the eBOSS Lyman-$\alpha$ forest survey. We use a new theoretical model and likelihood based on the PRIYA simulation suite. PRIYA is the first suite to resolve the Lyman-$\alpha$ forest…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 M. A. Fernandez , Simeon Bird , Ming-Feng Ho

A new method based on a Reverse Monte Carlo [RMC] technique and aimed at the inverse problem in the analysis of interstellar (intergalactic) absorption lines is presented. The line formation process in chaotic media with a finite…

Astrophysics · Physics 2022-03-23 S. A. Levshakov , W. H. Kegel , F. Takahara

Object recognition and reconstruction is of great interest in many research fields. Detecting pedestrians or cars in traffic cameras or tracking seismic waves in geophysical exploration are only two of many applications. Recently, the…

Numerical Analysis · Mathematics 2022-11-18 Florian Bossmann , Wenze Wu

In photoacoustic tomography, one is interested to recover the initial pressure distribution inside a tissue from the corresponding measurements of the induced acoustic wave on the boundary of a region enclosing the tissue. In the limited…

Numerical Analysis · Mathematics 2018-04-10 Florian Dreier , Sergiy Pereverzyev , Markus Haltmeier

Reconstructing 3D face from a single unconstrained image remains a challenging problem due to diverse conditions in unconstrained environments. Recently, learning-based methods have achieved notable results by effectively capturing complex…

Computer Vision and Pattern Recognition · Computer Science 2025-09-17 Danling Cao

Low-Rank Adaptation (LoRA) lowers the computational and memory overhead of fine-tuning large models by updating a low-dimensional subspace of the pre-trained weight matrix. Albeit efficient, LoRA exhibits suboptimal convergence and…

Machine Learning · Computer Science 2026-02-25 Yilang Zhang , Bingcong Li , Georgios B. Giannakis

Cosmological simulations with gas provide a detailed description of the intergalactic medium, making possible predictions of neutral hydrogen absorption in the spectra of background QSOs. We present results from a high-resolution…

Astrophysics · Physics 2009-10-28 Lars Hernquist , Neal Katz , David H. Weinberg , Jordi Miralda-Escude

In industrial applications, it is common to scan objects on a moving conveyor belt. If slice-wise 2D computed tomography (CT) measurements of the moving object are obtained we call it a sequential scanning geometry. In this case, each slice…

Signal Processing · Electrical Eng. & Systems 2023-11-10 Sebastian Springer , Aldo Glielmo , Angelina Senchukova , Tomi Kauppi , Jarkko Suuronen , Lassi Roininen , Heikki Haario , Andreas Hauptmann