Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation

Modern large-scale cosmological simulations model the universe with increasing sophistication and at higher spatial and temporal resolutions. These ongoing enhancements permit increasingly detailed comparisons between the simulation outputs and real observational data. Recent projects such as Illust...

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Main Authors: Dickinson, Hugh, Fortson, Lucy, Lintott, Chris, Scarlata, Claudia, Willett, Kyle, Bamford, Steven, Beck, Melanie, Cardamone, Carolin, Galloway, Melanie, Simmons, Brooke, Keel, William, Kruk, Sandor, Masters, Karen, Vogelsberger, Mark, Torrey, Paul, Snyder, Gregory F.
Format: Article
Published: American Astronomical Society 2018
Subjects:
Online Access:https://eprints.nottingham.ac.uk/50423/
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author Dickinson, Hugh
Fortson, Lucy
Lintott, Chris
Scarlata, Claudia
Willett, Kyle
Bamford, Steven
Beck, Melanie
Cardamone, Carolin
Galloway, Melanie
Simmons, Brooke
Keel, William
Kruk, Sandor
Masters, Karen
Vogelsberger, Mark
Torrey, Paul
Snyder, Gregory F.
author_facet Dickinson, Hugh
Fortson, Lucy
Lintott, Chris
Scarlata, Claudia
Willett, Kyle
Bamford, Steven
Beck, Melanie
Cardamone, Carolin
Galloway, Melanie
Simmons, Brooke
Keel, William
Kruk, Sandor
Masters, Karen
Vogelsberger, Mark
Torrey, Paul
Snyder, Gregory F.
author_sort Dickinson, Hugh
building Nottingham Research Data Repository
collection Online Access
description Modern large-scale cosmological simulations model the universe with increasing sophistication and at higher spatial and temporal resolutions. These ongoing enhancements permit increasingly detailed comparisons between the simulation outputs and real observational data. Recent projects such as Illustris are capable of producing simulated images that are designed to be comparable to those obtained from local surveys. This paper tests the degree to which Illustris achieves this goal across a diverse population of galaxies using visual morphologies derived from Galaxy Zoo citizen scientists. Morphological classifications provided by these volunteers for simulated galaxies are compared with similar data for a compatible sample of images drawn from the Sloan Digital Sky Survey (SDSS) Legacy Survey. This paper investigates how simple morphological characterization by human volunteers asked to distinguish smooth from featured systems differs between simulated and real galaxy images. Significant differences are identified, which are most likely due to the limited resolution of the simulation, but which could be revealing real differences in the dynamical evolution of populations of galaxies in the real and model universes. Specifically, for stellar masses, a substantially larger proportion of Illustris galaxies that exhibit disk-like morphology or visible substructure, relative to their SDSS counterparts. Toward higher masses, the visual morphologies for simulated and observed galaxies converge and exhibit similar distributions. The stellar mass threshold indicated by this divergent behavior confirms recent works using parametric measures of morphology from Illustris simulated images. When , the Illustris data set contains substantially fewer galaxies that classifiers regard as unambiguously featured. In combination, these results suggest that comparison between the detailed properties of observed and simulated galaxies, even when limited to reasonably massive systems, may be misleading.
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spelling nottingham-504232020-05-04T19:30:54Z https://eprints.nottingham.ac.uk/50423/ Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation Dickinson, Hugh Fortson, Lucy Lintott, Chris Scarlata, Claudia Willett, Kyle Bamford, Steven Beck, Melanie Cardamone, Carolin Galloway, Melanie Simmons, Brooke Keel, William Kruk, Sandor Masters, Karen Vogelsberger, Mark Torrey, Paul Snyder, Gregory F. Modern large-scale cosmological simulations model the universe with increasing sophistication and at higher spatial and temporal resolutions. These ongoing enhancements permit increasingly detailed comparisons between the simulation outputs and real observational data. Recent projects such as Illustris are capable of producing simulated images that are designed to be comparable to those obtained from local surveys. This paper tests the degree to which Illustris achieves this goal across a diverse population of galaxies using visual morphologies derived from Galaxy Zoo citizen scientists. Morphological classifications provided by these volunteers for simulated galaxies are compared with similar data for a compatible sample of images drawn from the Sloan Digital Sky Survey (SDSS) Legacy Survey. This paper investigates how simple morphological characterization by human volunteers asked to distinguish smooth from featured systems differs between simulated and real galaxy images. Significant differences are identified, which are most likely due to the limited resolution of the simulation, but which could be revealing real differences in the dynamical evolution of populations of galaxies in the real and model universes. Specifically, for stellar masses, a substantially larger proportion of Illustris galaxies that exhibit disk-like morphology or visible substructure, relative to their SDSS counterparts. Toward higher masses, the visual morphologies for simulated and observed galaxies converge and exhibit similar distributions. The stellar mass threshold indicated by this divergent behavior confirms recent works using parametric measures of morphology from Illustris simulated images. When , the Illustris data set contains substantially fewer galaxies that classifiers regard as unambiguously featured. In combination, these results suggest that comparison between the detailed properties of observed and simulated galaxies, even when limited to reasonably massive systems, may be misleading. American Astronomical Society 2018-02-05 Article PeerReviewed Dickinson, Hugh, Fortson, Lucy, Lintott, Chris, Scarlata, Claudia, Willett, Kyle, Bamford, Steven, Beck, Melanie, Cardamone, Carolin, Galloway, Melanie, Simmons, Brooke, Keel, William, Kruk, Sandor, Masters, Karen, Vogelsberger, Mark, Torrey, Paul and Snyder, Gregory F. (2018) Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation. Astrophysical Journal, 853 (2). 194/1-194/10. ISSN 1538-4357 cosmology: theory; galaxies: evolution; galaxies: fundamental parameters; galaxies: statistics; galaxies: structure http://iopscience.iop.org/article/10.3847/1538-4357/aaa250/meta doi:10.3847/1538-4357/aaa250 doi:10.3847/1538-4357/aaa250
spellingShingle cosmology: theory; galaxies: evolution; galaxies: fundamental parameters; galaxies: statistics; galaxies: structure
Dickinson, Hugh
Fortson, Lucy
Lintott, Chris
Scarlata, Claudia
Willett, Kyle
Bamford, Steven
Beck, Melanie
Cardamone, Carolin
Galloway, Melanie
Simmons, Brooke
Keel, William
Kruk, Sandor
Masters, Karen
Vogelsberger, Mark
Torrey, Paul
Snyder, Gregory F.
Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title_full Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title_fullStr Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title_full_unstemmed Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title_short Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation
title_sort galaxy zoo: morphological classification of galaxy images from the illustris simulation
topic cosmology: theory; galaxies: evolution; galaxies: fundamental parameters; galaxies: statistics; galaxies: structure
url https://eprints.nottingham.ac.uk/50423/
https://eprints.nottingham.ac.uk/50423/
https://eprints.nottingham.ac.uk/50423/