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We present a novel procedure to estimate the Equation of State of the intergalactic medium in the quasi-linear regime of structure formation based on Ly$\alpha$ forest tomography and apply it to 21 high quality quasar spectra from the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-07 Hendrik Müller , Christoph Behrens , David James Edward Marsh

We present a novel Bayesian method for the joint reconstruction of cosmological matter density fields, peculiar velocities and power-spectra in the quasi-nonlinear regime. We study its applicability to the Ly-alpha forest based on multiple…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Francisco-Shu Kitaura , Simona Gallerani , Andrea Ferrara

We discuss the implementation of Bayesian inversion methods in order to recover the properties of the intergalactic medium from observations of the neutral hydrogen Lyman-$\alpha$ absorptions observed in the spectra of high redshift quasars…

Astrophysics · Physics 2009-11-06 C. Pichon , J. L. Vergely , E. Rollinde , S. Colombi , P. Petitjean

The reconstruction of relative permittivity and conductivity in microwave tomography is carried out using regularized Gauss-Newton and Conjugate-Gradient iterative schemes. These two approaches are numerically tested and compared in terms…

Computational Physics · Physics 2019-10-25 Slimane Arhab

We introduce Intrinsic Image Fusion, a method that reconstructs high-quality physically based materials from multi-view images. Material reconstruction is highly underconstrained and typically relies on analysis-by-synthesis, which requires…

Computer Vision and Pattern Recognition · Computer Science 2026-03-24 Peter Kocsis , Lukas Höllein , Matthias Nießner

Cosmological hydrodynamic simulations can accurately predict the properties of the intergalactic medium (IGM), but only under the condition of retaining high spatial resolution necessary to resolve density fluctuations in the IGM. This…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Daniele Sorini , José Oñorbe , Zarija Lukić , Joseph F. Hennawi

We explore the use of Deep Learning to infer physical quantities from the observable transmitted flux in the Lyman-alpha forest. We train a Neural Network using redshift z=3 outputs from cosmological hydrodynamic simulations and mock…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-07 Lawrence Huang , Rupert A. C. Croft , Hitesh Arora

Visualizing the high-redshift Universe is difficult due to the dearth of available data; however, the Lyman-alpha forest provides a means to map the intergalactic medium at redshifts not accessible to large galaxy surveys. Large-scale…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Jessi Cisewski , Rupert A. C. Croft , Peter E. Freeman , Christopher R. Genovese , Nishikanta Khandai , Melih Ozbek , Larry Wasserman

Recent Lyman-$\alpha$ forest tomography measurements of the intergalactic medium (IGM) have revealed a wealth of cosmic structures at high redshift ($z\sim 2.5$). In this work, we present the Tomographic Absorption Reconstruction and…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-18 Benjamin Horowitz , Khee-Gan Lee , Martin White , Alex Krolewski , Metin Ata

We investigate several approaches to address the inverse problem that arises in the limited inverse Fourier transform (L-IDFT) of quasi-distributions. The methods explored include Tikhonov regularization, the Backus-Gilbert method, the…

High Energy Physics - Lattice · Physics 2025-11-13 Yu-Fei Ling , Min-Huan Chu , Jian Liang , Jun Hua , Ao-Sheng Xiong , Qi-An Zhang

We present a new iterative rotation inversion technique based on the Simultaneous Algebraic Reconstruction Technique developed for image reconstruction. We describe in detail our algorithmic implementation and compare it to the classical…

Solar and Stellar Astrophysics · Physics 2024-06-17 Sylvain G. Korzennik , Antonio Eff-Darwich

This study evaluates three reconstruction methods for sparse climate data: the simple inverse distance weighting (IDW), the statistically grounded ordinary kriging (OK), and the advanced implicit neural representation model (MMGN…

Machine Learning · Computer Science 2025-12-16 Jakub Walczak

The Richardson-Lucy method is the most popular deconvolution method in astronomy because it preserves the number of counts and the non-negativity of the original object. Regularization is, in general, obtained by an early stopping of…

Instrumentation and Methods for Astrophysics · Physics 2012-10-10 M. Prato , R. Cavicchioli , L. Zanni , P. Boccacci , M. Bertero

A method for the recovery of the real space line-of-sight mass density field from Lyman absorption in QSO spectra is presented. The method makes use of a Lucy-type algorithm for the recovery of the HI density. The matter density is inferred…

Astrophysics · Physics 2009-10-30 Adi Nusser , Martin Haehnelt

Observations of the Lyman-$\alpha$ (Ly$\alpha$) forest in spectra of distant quasars enable us to probe the matter power spectrum at relatively small scales. With several upcoming surveys, it is expected that there will be a many-fold…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Bhaskar Arya , Tirthankar Roy Choudhury , Aseem Paranjape , Prakash Gaikwad

We address the inverse problem of cosmic large-scale structure reconstruction from a Bayesian perspective. For a linear data model, a number of known and novel reconstruction schemes, which differ in terms of the underlying signal prior,…

Astrophysics · Physics 2009-11-06 F. S. Kitaura , T. A. Ensslin

Two maximum likelihood-based algorithms for unfolding or deconvolution are considered: the Richardson-Lucy method and the Data Unfolding method with Mean Integrated Square Error (MISE) optimization [10]. Unfolding is viewed as a procedure…

Data Analysis, Statistics and Probability · Physics 2025-11-18 Nikolay D. Gagunashvili

We propose a method for reconstruction of the density matrix from measurable time-dependent (probability) distributions of physical quantities. The applicability of the method based on least-squares inversion is - compared with other…

Quantum Physics · Physics 2016-09-08 T. Opatrny , D. -G. Welsch , W. Vogel

Low-dose tomography is highly preferred in medical procedures for its reduced radiation risk when compared to standard-dose Computed Tomography (CT). However, the lower the intensity of X-rays, the higher the acquisition noise and hence the…

Image and Video Processing · Electrical Eng. & Systems 2019-12-24 Preeti Gopal , Sharat Chandran , Imants Svalbe , Ajit Rajwade

We present a novel, fast method to recover the density field through the statistics of the transmitted flux in high redshift quasar absorption spectra. The proposed technique requires the computation of the probability distribution function…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Simona Gallerani , Francisco-Shu Kitaura , Andrea Ferrara
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