Measuring galaxy asymmetries in 3D

One of the commonly used non-parametric morphometric statistics for galaxy profiles and images is the asymmetry statistic. With an eye to current and upcoming large neutral hydrogen (H i) surveys, we develop a 3D version of the asymmetry statistic that can be applied to datacubes. This statistic is...

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Main Authors: Deg, N., Perron-Cormier, M., Spekkens, K., Glowacki, Marcin, Blyth, S.L., Hank, N.
Format: Journal Article
Published: 2023
Online Access:http://hdl.handle.net/20.500.11937/96441
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author Deg, N.
Perron-Cormier, M.
Spekkens, K.
Glowacki, Marcin
Blyth, S.L.
Hank, N.
author_facet Deg, N.
Perron-Cormier, M.
Spekkens, K.
Glowacki, Marcin
Blyth, S.L.
Hank, N.
author_sort Deg, N.
building Curtin Institutional Repository
collection Online Access
description One of the commonly used non-parametric morphometric statistics for galaxy profiles and images is the asymmetry statistic. With an eye to current and upcoming large neutral hydrogen (H i) surveys, we develop a 3D version of the asymmetry statistic that can be applied to datacubes. This statistic is more resilient to variations due to the observed geometry than 1D asymmetry measures, and can be successfully applied to lower spatial resolutions (3 - 4 beams across the galaxy major axis) than the 2D statistic. We have also modified the asymmetry definition from an 'absolute difference' version to a 'squared difference' version that removes much of the bias due to noise contributions for low signal-to-noise observations. Using a suite of mock asymmetric cubes we show that the background-corrected, squared difference 3D asymmetry statistic can be applied to many marginally resolved galaxies in large wide-area H i surveys such as WALLABY on the Australian SKA Pathfinder (ASKAP).
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spelling curtin-20.500.11937-964412024-12-17T06:22:16Z Measuring galaxy asymmetries in 3D Deg, N. Perron-Cormier, M. Spekkens, K. Glowacki, Marcin Blyth, S.L. Hank, N. One of the commonly used non-parametric morphometric statistics for galaxy profiles and images is the asymmetry statistic. With an eye to current and upcoming large neutral hydrogen (H i) surveys, we develop a 3D version of the asymmetry statistic that can be applied to datacubes. This statistic is more resilient to variations due to the observed geometry than 1D asymmetry measures, and can be successfully applied to lower spatial resolutions (3 - 4 beams across the galaxy major axis) than the 2D statistic. We have also modified the asymmetry definition from an 'absolute difference' version to a 'squared difference' version that removes much of the bias due to noise contributions for low signal-to-noise observations. Using a suite of mock asymmetric cubes we show that the background-corrected, squared difference 3D asymmetry statistic can be applied to many marginally resolved galaxies in large wide-area H i surveys such as WALLABY on the Australian SKA Pathfinder (ASKAP). 2023 Journal Article http://hdl.handle.net/20.500.11937/96441 10.1093/mnras/stad1693 http://purl.org/au-research/grants/arc/DP210102103 fulltext
spellingShingle Deg, N.
Perron-Cormier, M.
Spekkens, K.
Glowacki, Marcin
Blyth, S.L.
Hank, N.
Measuring galaxy asymmetries in 3D
title Measuring galaxy asymmetries in 3D
title_full Measuring galaxy asymmetries in 3D
title_fullStr Measuring galaxy asymmetries in 3D
title_full_unstemmed Measuring galaxy asymmetries in 3D
title_short Measuring galaxy asymmetries in 3D
title_sort measuring galaxy asymmetries in 3d
url http://hdl.handle.net/20.500.11937/96441