English
Related papers

Related papers: Ly$\alpha$NNA: A Deep Learning Field-level Inferen…

200 papers

In this paper we critically examine predictions of the Lya forest within the standard cold dark matter (SCDM) model, paying particular attention to the low end of the column-density distribution. We show in particular that the width of…

Astrophysics · Physics 2009-10-30 Greg L. Bryan , Marie Machacek , Peter Anninos , Michael L. Norman

We use the LUQAS sample of 27 high resolution, high signal-to-noise QSO absorption spectra (Kim et al. 2004) and the results from Croft et al. (2002) together with a suite of high-resolution hydro-dynamical simulations run with the…

When performing cosmological inference, standard analyses of the Lyman-$\alpha$ (Ly$\alpha$) three-dimensional correlation functions only consider the information carried by the distinct peak produced by baryon acoustic oscillations (BAO).…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Francesca Gerardi , Andrei Cuceu , Andreu Font-Ribera , Benjamin Joachimi , Pablo Lemos

Unpredictability of renewable energy sources coupled with the complexity of those methods used for various purposes in this area calls for the development of robust methods such as DL models within the renewable energy domain. Given the…

Machine Learning · Computer Science 2025-05-07 Lutfu Sua , Haibo Wang , Jun Huang

Deep learning (DL) models are gaining popularity in forest variable prediction using Earth Observation images. However, in practical forest inventories, reference datasets are often represented by plot- or stand-level measurements, while…

Signal Processing · Electrical Eng. & Systems 2023-08-10 Shaojia Ge , Oleg Antropov , Tuomas Häme , Ronald E. McRoberts , Jukka Miettinen

We present a general framework for obtaining robust bounds on the nature of dark matter using cosmological $N$-body simulations and Lyman-alpha forest data. We construct an emulator of hydrodynamical simulations, which is a flexible,…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-23 Keir K. Rogers , Hiranya V. Peiris

This study investigates the relationships which deep learning methods can identify between the input and output data. As a case study, rainfall-runoff modeling in a snow-dominated watershed by means of a long- and short-term memory (LSTM)…

Atmospheric and Oceanic Physics · Physics 2021-11-11 Kazuki Yokoo , Kei Ishida , Ali Ercan , Tongbi Tu , Takeyoshi Nagasato , Masato Kiyama , Motoki Amagasaki

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

We present the PRIYA suite of cosmological simulations, based on the code and hydrodynamic model of the ASTRID simulation, and designed for cosmological analyses of the Lyman-$\alpha$ forest. Our simulation suite spans a $9$-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-04 Simeon Bird , Martin Fernandez , Ming-Feng Ho , Mahdi Qezlou , Reza Monadi , Yueying Ni , Nianyi Chen , Rupert Croft , Tiziana Di Matteo

We propose a novel method for approximate inference in Bayesian networks (BNs). The idea is to sample data from a BN, learn a latent tree model (LTM) from the data offline, and when online, make inference with the LTM instead of the…

Machine Learning · Computer Science 2014-01-16 Yi Wang , Nevin L. Zhang , Tao Chen

We quantify the impact of massive neutrinos on the statistics of low density regions in the intergalactic medium (IGM) as probed by the Lyman-alpha forest at redshifts z=2.2--4. Based on mock but realistic quasar (QSO) spectra extracted…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 Francisco Villaescusa-Navarro , Mark Vogelsberger , Matteo Viel , Abraham Loeb

The Lyman alpha forest power spectrum has been measured on large scales by the BOSS survey in SDSS-III at $z\sim 2.3$, has been shown to agree well with linear theory predictions, and has provided the first measurement of Baryon Acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Andreu Arinyo-i-Prats , Jordi Miralda-Escudé , Matteo Viel , Renyue Cen

We use the Sherwood-Relics suite of hybrid hydrodynamical and radiative transfer simulations to model the effect of inhomogeneous reionisation on the 1D power spectrum of the \Lya forest transmitted flux at redshifts $4.2\leq z \leq 5$.…

We use an automated Voigt-profile fitting procedure to extract statistical properties of the Ly$\alpha$ forest in a numerical simulation of an $\Omega=1$, cold dark matter (CDM) universe. Our analysis method is similar to that used in most…

Astrophysics · Physics 2016-08-30 Romeel Davé , Lars Hernquist , David Weinberg , Neal Katz

We investigate Lyman-alpha (Ly$\alpha$) transmission spikes at $5.2 < z < 6.8$ using synthetic quasar spectra from the ``Cosmic Reionization On Computers" simulations. We focus on understanding the relationship between these spikes and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-01 Hanjue Zhu , Nickolay Gnedin , Camille Avestruz

The z > 2 Lyman-alpha (Lya) forest traces the underlying dark-matter distribution on large scales and, given sufficient sightlines, can be used to create 3D maps of large-scale structure. We examine the observational requirements to…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-23 Khee-Gan Lee , Joseph F. Hennawi , Martin White , Rupert Croft , Melih Ozbek

(abridged) We present an effective implementation of analytical calculations of the Lyalpha opacity distribution of the Intergalactic Medium (IGM) along multiple lines of sight (LOS) to distant quasars in a cosmological setting. This method…

Astrophysics · Physics 2009-11-06 M. Viel , S. Matarrese , H. J. Mo , M. G. Haehnelt , Tom Theuns

We model the $\lya$ forest in a spatially flat, CDM model with $\Omega=0.4$, with an Eulerian hydrodynamic simulation, and find that the intergalactic, photoionized gas collapses into sheet-like and filamentary structures which produce…

Astrophysics · Physics 2009-10-28 Jordi Miralda-Escude , Renyue Cen , Jeremiah P. Ostriker , Michael Rauch

We report the application of implicit likelihood inference to the prediction of the macro-parameters of strong lensing systems with neural networks. This allows us to perform deep learning analysis of lensing systems within a well-defined…

Instrumentation and Methods for Astrophysics · Physics 2023-01-25 Ronan Legin , Yashar Hezaveh , Laurence Perreault-Levasseur , Benjamin Wandelt

Deep forest is a non-differentiable deep model which has achieved impressive empirical success across a wide variety of applications, especially on categorical/symbolic or mixed modeling tasks. Many of the application fields prefer…

Machine Learning · Computer Science 2023-05-02 Yi-Xiao He , Shen-Huan Lyu , Yuan Jiang