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The immense amount of time series data produced by astronomical surveys has called for the use of machine learning algorithms to discover and classify several million celestial sources. In the case of variable stars, supervised learning…

Solar and Stellar Astrophysics · Physics 2022-10-12 R. Pantoja , M. Catelan , K. Pichara , P. Protopapas

As available data sets grow in size and complexity, advanced visualization tools enabling their exploration and analysis become more important. In modern astronomy, integral field spectroscopic galaxy surveys are a clear example of…

The outskirts of galaxy clusters are characterised by the interplay of gas accretion and dynamical evolution involving turbulence, shocks, magnetic fields and diffuse radio emission. The density and velocity structure of the gas in the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-29 Luigi Iapichino , Christoph Federrath , Ralf S. Klessen

We present a new method for reconstructing two-dimensional mass maps of galaxy clusters from the image distortion of background galaxies. In contrast to most previous approaches, which directly convert locally averaged image ellipticities…

Astrophysics · Physics 2007-05-23 Stella Seitz , Peter Schneider , Matthias Bartelmann

An extensive redshift survey has been conducted on a sample of 15 nearby (0.01 < z < 0.05) clusters of galaxies. A total number of 860 redshifts were determined by fitting of emission--lines and/or cross-correlation techniques. Of this…

Astrophysics · Physics 2007-05-23 P. Stein

We present a technique for estimating the mass in the outskirts of galaxy clusters where the usual assumption of dynamical equilibrium is not valid. The method assumes that clusters form through hierarchical clustering and requires only…

Astrophysics · Physics 2009-10-31 Antonaldo Diaferio

The physical properties of the intracluster medium (ICM) reflect signatures of the underlying gravitational potential, mergers and strong interactions with other halos and satellite galaxies, as well as galactic feedback from supernovae and…

Astrophysics of Galaxies · Physics 2026-05-27 Urmila Chadayammuri , Lukas Eisert , Annalisa Pillepich , Katrin Lehle , Mohammadreza Ayromlou , Dylan Nelson

Hydrodynamical simulations play a fundamental role in modern cosmological research, serving as a crucial bridge between theoretical predictions and observational data. However, due to their computational intensity, these simulations are…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-12 Andrés Caro , Daniel de Andres , Weiguang Cui , Gustavo Yepes , Marco De Petris , Antonio Ferragamo , Félicien Schiltz , Amélie Nef

We develop a machine learning algorithm that generates high-resolution thermal Sunyaev-Zeldovich (SZ) maps of novel galaxy clusters given only halo mass and mass accretion rate. The algorithm uses a conditional variational autoencoder…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 Tibor Rothschild , Daisuke Nagai , Han Aung , Sheridan B. Green , Michelle Ntampaka , John ZuHone

Structural properties posses valuable information about the formation and evolution of galaxies, and are important for understanding the past, present, and future universe. Here we use unsupervised machine learning methodology to analyze a…

Instrumentation and Methods for Astrophysics · Physics 2015-05-26 Andrew Schutter , Lior Shamir

As we enter the era of large imaging surveys such as $\textit{Roman}$, Rubin, and $\textit{Euclid}$, a deeper understanding of potential biases and selection effects in optical astronomical catalogs created with the use of ML-based methods…

We present a novel method to recontruct the mass distribution of galaxy clusters from their gravitational lens effect on background galaxies. The method is based on a least-chisquare fit of the two-dimensional gravitational cluster…

Astrophysics · Physics 2009-10-28 Matthias Bartelmann , Ramesh Narayan , Stella Seitz , Peter Schneider

We apply a methodology to build a sample of extreme emission line galaxies (EELGs) using integral field spectroscopy data. In this work we follow the spectroscopic criteria corresponding for EELG selection and use the MUSE Hubble Ultra-Deep…

Astrophysics of Galaxies · Physics 2024-07-31 I. del Moral-Castro , J. M. Vílchez , J. Iglesias-Páramo , A. Arroyo-Polonio

Significant galaxy mergers throughout cosmic time play a fundamental role in theories of galaxy evolution. The widespread usage of human classifiers to visually assess whether galaxies are in merging systems remains a fundamental component…

We applied the image-based approach with a convolutional neural network model to the sample of low-redshifts galaxies with $-24^{m}<M_{r}<-19.4^{m}$ from the SDSS DR9. We divided it into two subsamples, SDSS DR9 galaxy dataset and Galaxy…

Astrophysics of Galaxies · Physics 2022-08-04 I. B. Vavilova , V. Khramtsov , D. V. Dobrycheva , M. Yu. Vasylenko , A. A. Elyiv , O. V. Melnyk

We investigate machine learning (ML) techniques for predicting the number of galaxies (N_gal) that occupy a halo, given the halo's properties. These types of mappings are crucial for constructing the mock galaxy catalogs necessary for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Xiaoying Xu , Shirley Ho , Hy Trac , Jeff Schneider , Barnabas Poczos , Michelle Ntampaka

I review here past and present research on clusters and groups of galaxies within the Sloan Digital Sky Survey (SDSS). In particular, I discuss the C4 algorithm which is designed to search for clusters within a 7-dimensional data-space,…

Astrophysics · Physics 2007-05-23 Robert C. Nichol

A significant degree of misclassification of variable stars through the application of machine learning methods to survey data motivates a search for more reliable and accurate machine learning procedures, especially in light of the very…

Solar and Stellar Astrophysics · Physics 2019-06-18 Refilwe Kgoadi , Chris Engelbrecht , Ian Whittingham , Andrew Tkachenko

We test the hypothesis that globular clusters form in supergiant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that such large, dense, and cold gas clouds assemble naturally in current hierarchical models…

Astrophysics · Physics 2010-07-27 Oleg Y. Gnedin , Jose L. Prieto