English
Related papers

Related papers: Classifying the formation processes of S0 galaxies…

200 papers

There is an obvious need for automated classification of galaxies, as the number of observed galaxies increases very fast. We examine several approaches to this problem, utilising {\em Artificial Neural Networks} (ANNs). We quote results…

Astrophysics · Physics 2009-10-22 Avi Naim

We present a framework to systematically analyze convolutional neural networks (CNNs) used in classification of cars in autonomous vehicles. Our analysis procedure comprises an image generator that produces synthetic pictures by sampling in…

Computer Vision and Pattern Recognition · Computer Science 2017-08-14 Tommaso Dreossi , Shromona Ghosh , Alberto Sangiovanni-Vincentelli , Sanjit A. Seshia

We developed a Deep Convolutional Neural Network (CNN), used as a classifier, to estimate photometric redshifts and associated probability distribution functions (PDF) for galaxies in the Main Galaxy Sample of the Sloan Digital Sky Survey…

Instrumentation and Methods for Astrophysics · Physics 2018-12-26 Johanna Pasquet , Emmanuel Bertin , Marie Treyer , Stéphane Arnouts , Dominique Fouchez

In this paper we present a methodology that uses convolutional neural networks (CNNs) for segmentation by iteratively growing predicted mask regions in each coordinate direction. The CNN is used to predict class probability scores in a…

Image and Video Processing · Electrical Eng. & Systems 2020-09-25 John Lagergren , Erica Rutter , Kevin Flores

Over the past decade deep learning has revolutionized the field of computer vision, with convolutional neural network models proving to be very effective for image classification benchmarks. However, a fundamental theoretical questions…

Computer Vision and Pattern Recognition · Computer Science 2023-07-04 Vinoth Nandakumar , Arush Tagade , Tongliang Liu

We are investigating the co-evolution of galaxies within groups combining multi-wavelength photometric and 2D kinematical observations. Here we focus on S0s showing star formation in ring/arm-like structures. We use smooth particle…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 P. Mazzei , A. Marino , R. Rampazzo , G. Galletta , D. Bettoni

In recent decades, large-scale sky surveys such as Sloan Digital Sky Survey (SDSS) have resulted in generation of tremendous amount of data. The classification of this enormous amount of data by astronomers is time consuming. To simplify…

Instrumentation and Methods for Astrophysics · Physics 2022-11-02 Sarvesh Gharat , Yogesh Dandawate

At high redshift, due to both observational limitations and the variety of galaxy morphologies in the early universe, measuring galaxy structure can be challenging. Non-parametric measurements such as the CAS system have thus become an…

Astrophysics of Galaxies · Physics 2021-09-08 C. Tohill , L. Ferreira , C. J. Conselice , S. P. Bamford , F. Ferrari

We present a new exploratory framework to model galaxy formation and evolution in a hierarchical universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and…

Astrophysics of Galaxies · Physics 2015-11-30 Harshil M. Kamdar , Matthew J. Turk , Robert J. Brunner

We use Bayesian convolutional neural networks and a novel generative model of Galaxy Zoo volunteer responses to infer posteriors for the visual morphology of galaxies. Bayesian CNN can learn from galaxy images with uncertain labels and…

We analyze the optical morphologies of galaxies in the IllustrisTNG simulation at $z\sim0$ with a Convolutional Neural Network trained on visual morphologies in the Sloan Digital Sky Survey. We generate mock SDSS images of a mass complete…

Contamination from galaxy fragments, identified as sources, is a major issue in large photometric galaxy catalogs. In this paper, we prove that this problem can be easily addressed with computer vision techniques. We use image cutouts to…

Astrophysics of Galaxies · Physics 2023-03-01 Enrico M. Di Teodoro , Josh E. G. Peek , John F. Wu

Determining the material category of a surface from an image is a demanding task in perception that is drawing increasing attention. Following the recent remarkable results achieved for image classification and object detection utilising…

Computer Vision and Pattern Recognition · Computer Science 2017-03-17 Grigorios Kalliatakis , Georgios Stamatiadis , Shoaib Ehsan , Ales Leonardis , Juergen Gall , Anca Sticlaru , Klaus D. McDonald-Maier

We present the results of a numerical adaptive mesh refinement hydrodynamical and N-body simulation in a $\Lambda CDM$ cosmology. We focus on the analysis of the main properties of massive galaxies ($M_* > 10^{11}\,M_{\odot}$) at $z=0$. For…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Javier Navarro-González , Elena Ricciardelli , Vicent Quilis , Alexandre Vazdekis

Cosmological galaxy formation simulations are powerful tools to understand the complex processes that govern the formation and evolution of galaxies. However, evaluating the realism of these simulations remains a challenge. The two common…

Convolutional neural networks (CNNs) are widely used for image recognition and text analysis, and have been suggested for application on one-dimensional data as a way to reduce the need for pre-processing steps. Pre-processing is an…

Machine Learning · Computer Science 2020-05-18 Ine L. Jernelv , Dag Roar Hjelme , Yuji Matsuura , Astrid Aksnes

Cosmological galaxy formation simulations are still limited by their spatial/mass resolution and cannot model from first principles some of the processes, like star formation, that are key in driving galaxy evolution. As a consequence they…

Astrophysics of Galaxies · Physics 2022-03-02 Andrea V. Macciò , Mohamad Ali-Dib , Pavle Vulanović , Hind Al Noori , Fabian Walter , Nico Krieger , Tobias Buck

A significant fraction of high redshift star-forming disc galaxies are known to host giant clumps, whose nature and role in galaxy evolution are yet to be understood. In this work we first present a new method based on neural networks to…

Galaxies play a key role in our endeavor to understand how structure formation proceeds in the Universe. For any precision study of cosmology or galaxy formation, there is a strong demand for huge sets of realistic mock galaxy catalogs,…

Astrophysics of Galaxies · Physics 2023-11-16 Chen-Yu Chuang , Christian Kragh Jespersen , Yen-Ting Lin , Shirley Ho , Shy Genel

We test the theory that lenticular (S0) galaxies form from spirals whose star formation has been shut down. We use the globular cluster specific frequency S_N, defined as the number of globular clusters normalised by the galaxy luminosity…

Astrophysics · Physics 2009-11-13 J. M. Barr , A. G. Bedregal , A. Aragon-Salamanca , M. R. Merrifield , S. P. Bamford