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Related papers: Classifying galaxies according to their HI content

200 papers

This is the second paper of two reporting results from a study of the HI content and stellar properties of nearby galaxies detected by the Arecibo Legacy Fast ALFA blind 21-cm line survey and the Sloan Digital Sky Survey in a 2160 deg^2…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. C. Toribio , J. M. Solanes , R. Giovanelli , M. P. Haynes , A. Martin

Upcoming 21cm surveys will map the spatial distribution of cosmic neutral hydrogen (HI) over unprecedented volumes. Mock catalogues are needed to fully exploit the potential of these surveys. Standard techniques employed to create these…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-02 Digvijay Wadekar , Francisco Villaescusa-Navarro , Shirley Ho , Laurence Perreault-Levasseur

We report results from a study of the HI content and stellar properties of nearby galaxies detected by the Arecibo Legacy Fast ALFA blind 21-cm line survey and the Sloan Digital Sky Survey in two declination strips covering a total area of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. C. Toribio , J. M. Solanes , R. Giovanelli , M. P. Haynes , K. L. Masters

Due to the fact that HI mass measurements are not available for large galaxy samples at high redshifts, we apply a photometric estimator of the HI-to-stellar mass ratio (M_HI/M_*) calibrated using a local Universe sample of galaxies to a…

Astrophysics of Galaxies · Physics 2021-04-07 Wei Zhang , Guinevere Kauffmann , Jing Wang , Yanmei Chen , Jian Fu , Hong Wu

We report the first results of a programme aimed at studying the properties of high redshift galaxies with on-going massive and dominant episodes of star formation (HII galaxies). We use the $L(\mathrm{H}\beta) - \sigma$ distance estimator…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Roberto Terlevich , Elena Terlevich , Jorge Melnick , Ricardo Chávez , Manolis Plionis , Fabio Bresolin , Spyros Basilakos

There exist a variety of star-galaxy classification techniques, each with their own strengths and weaknesses. In this paper, we present a novel meta-classification framework that combines and fully exploits different techniques to produce a…

Instrumentation and Methods for Astrophysics · Physics 2015-08-20 Edward J. Kim , Robert J. Brunner , Matias Carrasco Kind

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

We investigate the properties of HI-rich galaxies detected in blind radio surveys within the hierarchical structure formation scenario using a semi-analytic model of galaxy formation. By drawing a detailed comparison between the properties…

Astrophysics of Galaxies · Physics 2015-05-18 Katsuya Okoshi , Masahiro Nagashima , Naoteru Gouda , Yousuke Minowa

We present a star/galaxy classification for the Southern Photometric Local Universe Survey (S-PLUS), based on a Machine Learning approach: the Random Forest algorithm. We train the algorithm using the S-PLUS optical photometry up to $r$=21,…

Galaxies in the early Universe were more compact and contained more molecular gas than today. In this paper, we revisit the relation between these empirical findings, and we quantitatively predict the cosmic evolution of the surface…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-09 Danail Obreschkow , Steve Rawlings

Identifying galaxy groups from redshift surveys of galaxies plays an important role in connecting galaxies with the underlying dark matter distribution. Current and future high-$z$ spectroscopic surveys, usually incomplete in redshift…

Astrophysics of Galaxies · Physics 2020-10-14 Kai Wang , H. J. Mo , Cheng Li , Jiacheng Meng , Yangyao Chen

Low surface brightness substructures around galaxies, known as tidal features, are a valuable tool in the detection of past or ongoing galaxy mergers, and their properties can answer questions about the progenitor galaxies involved in the…

Astrophysics of Galaxies · Physics 2024-06-06 Alice Desmons , Sarah Brough , Francois Lanusse

Obtaining accurate photometric redshift estimations is an important aspect of cosmology, remaining a prerequisite of many analyses. In creating novel methods to produce redshift estimations, there has been a shift towards using machine…

Instrumentation and Methods for Astrophysics · Physics 2021-07-07 Ben Henghes , Connor Pettitt , Jeyan Thiyagalingam , Tony Hey , Ofer Lahav

We examine the global HI properties of galaxies in quarter-billion particle cosmological simulations using Gadget-2, focusing on how galactic outflows impact HI content. We consider four outflow models, including a new one (ezw) motivated…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Romeel Davé , Neal Katz , Benjamin D. Oppenheimer , Juna A. Kollmeier , David H. Weinberg

In this work, we study the basic statistical properties of HI-selected galaxies extracted from six different semi-analytic models, all run on the same cosmological N-body simulation. One model includes an explicit treatment for the…

Astrophysics of Galaxies · Physics 2016-12-21 Anna Zoldan , Gabriella De Lucia , Lizhi Xie , Fabio Fontanot , Michaela Hirschmann

Asymmetry in the spatially integrated, 1D HI global profiles of galaxies can inform us on both internal (e.g. outflows) and external (e.g. mergers, tidal interactions, ram pressure stripping) processes that shape galaxy evolution.…

Astrophysics of Galaxies · Physics 2022-10-05 M. Glowacki , N. Deg , S. L. Blyth , N. Hank , R. Davé , E. Elson , K. Spekkens

Machine learning (ML) techniques, in particular supervised regression algorithms, are a promising new way to use multiple observables to predict a cluster's mass or other key features. To investigate this approach we use the \textsc{MACSIS}…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-16 Thomas J. Armitage , Scott T. Kay , David J. Barnes

We present a comprehensive analysis of atomic hydrogen (HI) properties using a semi-analytical model of galaxy formation and N-body simulations covering a large cosmological volume at high resolution. We examine the HI mass function and the…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-11 Marta Spinelli , Anna Zoldan , Gabriella De Lucia , Lizhi Xie , Matteo Viel

Galaxy-scale strong lenses in galaxy clusters provide a unique tool to investigate their inner mass distribution and the sub-halo density profiles in the low-mass regime, which can be compared with the predictions from cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 G. Angora , P. Rosati , M. Meneghetti , M. Brescia , A. Mercurio , C. Grillo , P. Bergamini , A. Acebron , G. Caminha , M. Nonino , L. Tortorelli , L. Bazzanini , E. Vanzella

The universe is composed of galaxies that have diverse shapes. Once the structure of a galaxy is determined, it is possible to obtain important information about its formation and evolution. Morphologically classifying galaxies means…

Astrophysics of Galaxies · Physics 2026-04-23 N. M. Cardoso , G. B. O. Schwarz , L. O. Dias , C. R. Bom , L. Sodré , C. Mendes de Oliveira