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Some of the issues that make sampling parameter spaces of various beyond the Standard Model (BSM) scenarios computationally expensive are the high dimensionality of the input parameter space, complex likelihoods, and stringent experimental…

High Energy Physics - Phenomenology · Physics 2026-02-16 Atrideb Chatterjee , Arghya Choudhury , Sourav Mitra , Arpita Mondal , Subhadeep Mondal

We present a simulation-based inference (SBI) cosmological analysis of cosmic shear two-point statistics from the fourth weak gravitational lensing data release of the ESO Kilo-Degree Survey (KiDS-1000). KiDS-SBI efficiently performs…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-19 Maximilian von Wietersheim-Kramsta , Kiyam Lin , Nicolas Tessore , Benjamin Joachimi , Arthur Loureiro , Robert Reischke , Angus H. Wright

Simulation-based inference (SBI) is a powerful inference technique for cases where the exact functional form of the likelihood is not known. A prime example is the likelihood of cross-correlation power spectra of the cosmic microwave…

We present a Bayesian inference on the neutral hydrogen fraction of the intergalactic medium (IGM), $x_{\textrm{HI}}$, at $z \sim$ 6-8 using the properties of Lyman break galaxies during the Epoch of Reionization. We use large samples of…

We present the first simulation-based inference (SBI) of cosmological parameters from field-level analysis of galaxy clustering. Standard galaxy clustering analyses rely on analyzing summary statistics, such as the power spectrum, $P_\ell$,…

Simulation-based inference (SBI) methods typically require fully observed data to infer parameters of models with intractable likelihood functions. However, datasets often contain missing values due to incomplete observations, data…

Machine Learning · Computer Science 2025-03-04 Yogesh Verma , Ayush Bharti , Vikas Garg

Scientists and engineers use simulators to model empirically observed phenomena. However, tuning the parameters of a simulator to ensure its outputs match observed data presents a significant challenge. Simulation-based inference (SBI)…

We use state-of-the-art hydrodynamical simulations combined with a 1D radiative transfer code to assess the extent to which the highly ionized regions observed close to z~6 quasars, which we refer to as near-zones, can constrain the…

Astrophysics · Physics 2008-11-26 James S. Bolton , Martin G. Haehnelt

We demonstrate the successful use of scattering representations without further compression for simulation-based inference (SBI) with images (i.e. field-level), illustrated with a cosmological case study. Scattering representations provide…

Machine Learning · Computer Science 2024-12-03 Kiyam Lin , Benjamin Joachimi , Jason D. McEwen

We show how cross-correlating a high redshift external tracer field, such as the 21cm neutral hydrogen distribution and product maps involving Cosmic Microwave Background (CMB) temperature and polarisation fields, that probe mixed…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-07 D. Munshi , P. S. Corasaniti , P. Coles , A. Heavens , S. Pandolfi

We use hydrodynamic cosmological simulations in a 9.6 Mpc box to explore the evolution of the intergalactic medium (IGM) transmissivity from z=2 through the epoch of reionization. Reionization is achieved through an ultraviolet background…

Astrophysics · Physics 2009-11-10 Pascal Paschos , Michael L. Norman

We provide measurements of the neutral hydrogen fraction xHI at z~6, by comparing semi-analytical models of the Lyalpha forest with observations of high-z quasars and Gamma Ray Bursts absorption spectra. We analyze the transmitted flux in a…

Astrophysics · Physics 2010-11-11 S. Gallerani , A. Ferrara , X. Fan , Choudhury T. Roy , R. Salvaterra

We study the process of cosmic reionization and estimate the ionizing background in the IGM using the Lyman series absorption in the spectra of the four quasars at 5.7<z<6.3 discovered by the SDSS. We derive the evolution of the ionizing…

JWST provides a unique dataset to study reionization's earliest stages, promising insights into the first galaxies. Many JWST/NIRSpec prism spectra reveal smooth Lyman-alpha breaks in z>5 galaxies, implying damping wing scattering by…

Astrophysics of Galaxies · Physics 2026-01-14 Charlotte A. Mason , Zuyi Chen , Daniel P. Stark , Ting-Yi Lu , Michael Topping , Mengtao Tang

Simulation-based Bayesian inference (SBI) can be used to estimate the parameters of complex mechanistic models given observed model outputs without requiring access to explicit likelihood evaluations. A prime example for the application of…

Machine Learning · Computer Science 2022-11-28 Jonas Beck , Michael Deistler , Yves Bernaerts , Jakob Macke , Philipp Berens

The role played by the intergalactic medium (IGM) in the X-ray absorption towards high-redshift sources has recently drawn more attention in spectral analysis studies. Here, we study the X-ray absorption towards 15 flat-spectrum radio…

High Energy Astrophysical Phenomena · Physics 2018-09-05 R. Arcodia , S. Campana , R. Salvaterra , G. Ghisellini

Identifying tire and vehicle parameters is an essential step in designing control and planning algorithms for autonomous vehicles. This paper proposes a new method: Simulation-Based Inference (SBI), a modern interpretation of Approximate…

Robotics · Computer Science 2021-08-30 Ali Boyali , Simon Thompson , David Robert Wong

We present COMPASS, a novel simulation-based inference framework that combines score-based diffusion models with transformer architectures to jointly perform parameter estimation and Bayesian model comparison across competing Galactic…

Astrophysics of Galaxies · Physics 2025-07-09 Berkay Gunes , Sven Buder , Tobias Buck

A possible way to study the reionization of cosmic hydrogen is by observing the large ionized regions (bubbles) around bright individual sources, e.g., quasars, using the redshifted 21 cm signal. It has already been shown that matched…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Raghunath Ghara , T. Roy Choudhury

We develop the framework of Linear Simulation-based Inference (LSBI), an application of simulation-based inference where the likelihood is approximated by a Gaussian linear function of its parameters. We obtain analytical expressions for…

Instrumentation and Methods for Astrophysics · Physics 2025-01-08 Nicolas Mediato-Diaz , Will Handley
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