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Related papers: Bayesian fitting of multi-Gaussian expansion model…

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We describe a simple, efficient, robust and fully automatic algorithm for the determination of a Multi-Gaussian Expansion (MGE) fit to galaxy images, to be used as a parametrization for the galaxy stellar surface brightness. In most cases…

Astrophysics · Physics 2011-07-18 Michele Cappellari

In a strong gravitational lensing system, the distorted light from a source is analysed to infer the properties of the lens. However, light emitted by the lens itself can contaminate the image of the source, introducing systematic errors in…

Exponential, de Vaucouleurs, and S\'ersic profiles are simple and successful models for fitting two-dimensional images of galaxies. One numerical issue encountered in this kind of fitting is the pixel rendering and convolution (or…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 David W. Hogg , Dustin Lang

The Bayesian gravitational shear estimation algorithm developed by Bernstein and Armstrong (2014) can potentially be used to overcome multiplicative noise bias and recover shear using very low signal-to-noise ratio (S/N) galaxy images. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Erin S. Sheldon

The principles of measuring the shapes of galaxies by a model-fitting approach are discussed in the context of shape-measurement for surveys of weak gravitational lensing. It is argued that such an approach should be optimal, allowing…

Astrophysics · Physics 2009-11-13 L. Miller , T. D. Kitching , C. Heymans , A. F. Heavens , L. Van Waerbeke

Fitting the multi-wavelength spectral energy distributions (SEDs) of galaxies is a widely used technique to extract information about the physical properties of galaxies. However, a major difficulty lies in the numerous uncertainties…

Astrophysics of Galaxies · Physics 2020-06-17 Yunkun Han , Zhanwen Han , Lulu Fan

Structural parameters are normally extracted from observed galaxies by fitting analytic light profiles to the observations. Obtaining accurate fits to high-resolution images is a computationally expensive task, requiring many model…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 Benjamin R. Barsdell , David G. Barnes , Christopher J. Fluke

We present a newly developed version of BayeSED, a general Bayesian approach to the spectral energy distribution (SED) fitting of galaxies. The new BayeSED code has been systematically tested on a mock sample of galaxies. The comparison…

Astrophysics of Galaxies · Physics 2014-10-13 Yunkun Han , Zhanwen Han

In image reconstruction, an accurate quantification of uncertainty is of great importance for informed decision making. Here, the Bayesian approach to inverse problems can be used: the image is represented through a random function that…

Numerical Analysis · Mathematics 2025-04-24 Jonas Latz , Aretha L. Teckentrup , Simon Urbainczyk

In this paper, we describe a procedure for modelling strong lensing galaxy clusters with parametric methods, and to rank models quantitatively using the Bayesian evidence. We use a publicly available Markov chain Monte-Carlo (MCMC) sampler…

We introduce PHI, a fully Bayesian Markov-chain Monte Carlo algorithm designed for the structural decomposition of galaxy images. PHI uses a triple layer approach to effectively and efficiently explore the complex parameter space. Combining…

Astrophysics of Galaxies · Physics 2018-07-11 J. J. Argyle , J. Méndez-Abreu , V. Wild , D. J. Mortlock

Historically, metallicity profiles of galaxies have been modelled using a radially symmetric, two-parameter linear model, which reveals that most galaxies are more metal-rich in their central regions than their outskirts. However, this…

Instrumentation and Methods for Astrophysics · Physics 2024-03-14 Benjamin Metha , Simon Birrer , Tommaso Treu , Michele Trenti , Xuheng Ding , Xin Wang

Future cosmological galaxy surveys such as the Large Synoptic Survey Telescope (LSST) will photometrically observe very large numbers of galaxies. Without spectroscopy, the redshifts required for the analysis of these data will need to be…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-07 Daniel M. Jones , Alan F. Heavens

We introduce a novel machine learning framework for estimating the Bayesian posteriors of morphological parameters for arbitrarily large numbers of galaxies. The Galaxy Morphology Posterior Estimation Network (GaMPEN) estimates values and…

I describe a new, open-source astronomical image-fitting program called Imfit, specialized for galaxies but potentially useful for other sources, which is fast, flexible, and highly extensible. A key characteristic of the program is an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Peter Erwin

Gaussian graphical models are widely used to infer dependence structures. Bayesian methods are appealing to quantify uncertainty associated with structural learning, i.e., the plausibility of conditional independence statements given the…

Methodology · Statistics 2025-11-05 Deborah Sulem , Jack Jewson , David Rossell

Star-galaxy classification is one of the most fundamental data-processing tasks in survey astronomy, and a critical starting point for the scientific exploitation of survey data. For bright sources this classification can be done with…

Instrumentation and Methods for Astrophysics · Physics 2013-07-30 Marc Henrion , Daniel J. Mortlock , David J. Hand , Axel Gandy

One of the fundamental tasks of science is to find explainable relationships between observed phenomena. One approach to this task that has received attention in recent years is based on probabilistic graphical modelling with sparsity…

Machine Learning · Statistics 2014-04-16 Peter Orchard , Felix Agakov , Amos Storkey

We derive an estimator of weak gravitational lensing shear from background galaxy images that avoids noise-induced biases through a rigorous Bayesian treatment of the measurement. The derived shear estimator disposes with the assignment of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Gary M. Bernstein , Robert Armstrong

Dissecting the underlying structure of galaxies is of main importance in the framework of galaxy formation and evolution theories. While a classical bulge+disc decomposition of disc galaxies is usually taken as granted, this is only rarely…

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