The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model
We present a novel Bayesian method, referred to as BLOBBY3D, to infer gas kinematics that mitigates the effects of beam smearing for observations using integral field spectroscopy. The method is robust for regularly rotating galaxies despite substructure in the gas distribution. Modelling the gas su...
Published in: | Monthly Notices of the Royal Astronomical Society |
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Main Authors: | , , , , , , , , , , , , , , , , , , , , , , |
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Format: | Article in Journal/Newspaper |
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Oxford University Press (OUP)
2019
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Online Access: | http://hdl.handle.net/1959.3/450023 https://doi.org/10.1093/mnras/stz670 |
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ftswinburne:tle:eabd721d-d648-4f7e-ae3e-7f5561f41c32:28f49f06-0da8-44be-9edc-ad1dd0a9c582:1 |
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ftswinburne:tle:eabd721d-d648-4f7e-ae3e-7f5561f41c32:28f49f06-0da8-44be-9edc-ad1dd0a9c582:1 2023-05-15T18:11:35+02:00 The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model Varidel, Mathew R. Croom, Scott M. Lewis, Geraint F. Brewer, Brendon J. Di Teodoro, Enrico M. Bland-Hawthorn, Joss Bryant, Julia J. Federrath, Christoph Foster, Caroline Glazebrook, Karl Goodwin, Michael Groves, Brent Hopkins, Andrew M. Lawrence, Jon S. Lopez-Ssnchez, Angel R. Medling, Anne M. Owers, Matt S. Richards, Samuel N. Scalzo, Richard Scott, Nicholas Sweet, Sarah M. Taranu, Dan S. van de Sande, Jesse Swinburne University of Technology 2019 http://hdl.handle.net/1959.3/450023 https://doi.org/10.1093/mnras/stz670 unknown Oxford University Press (OUP) http://purl.org/au-research/grants/arc/CE170100013 http://purl.org/au-research/grants/arc/CE110001020 http://purl.org/au-research/grants/arc/DP160100723 http://purl.org/au-research/grants/arc/FT180100231 http://purl.org/au-research/grants/arc/DP170100603 http://purl.org/au-research/grants/arc/FT180100495 http://purl.org/au-research/grants/arc/FT140101202 http://purl.org/au-research/grants/arc/FT140100255 http://hdl.handle.net/1959.3/450023 https://doi.org/10.1093/mnras/stz670 This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. Copyright © 2019 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Monthly Notices of the Royal Astronomical Society, Vol. 485, no. 3 (May 2019), pp. 4024-4044 Journal article 2019 ftswinburne https://doi.org/10.1093/mnras/stz670 2019-09-07T21:10:37Z We present a novel Bayesian method, referred to as BLOBBY3D, to infer gas kinematics that mitigates the effects of beam smearing for observations using integral field spectroscopy. The method is robust for regularly rotating galaxies despite substructure in the gas distribution. Modelling the gas substructure within the disc is achieved by using a hierarchical Gaussian mixture model. To account for beam smearing effects, we construct a modelled cube that is then convolved per wavelength slice by the seeing, before calculating the likelihood function. We show that our method can model complex gas substructure including clumps and spiral arms. We also show that kinematic asymmetries can be observed after beam smearing for regularly rotating galaxies with asymmetries only introduced in the spatial distribution of the gas. We present findings for our method applied to a sample of 20 star-forming galaxies from the SAMI Galaxy Survey. We estimate the global H α gas velocity dispersion for our sample to be in the range σ¯v ∼[7, 30] km s−1. The relative difference between our approach and estimates using the single Gaussian component fits per spaxel is σ¯v/σ¯v = −0.29 ± 0.18 for the H α flux-weighted mean velocity dispersion. Article in Journal/Newspaper sami Swinburne University of Technology: Swinburne Research Bank Monthly Notices of the Royal Astronomical Society 485 3 4024 4044 |
institution |
Open Polar |
collection |
Swinburne University of Technology: Swinburne Research Bank |
op_collection_id |
ftswinburne |
language |
unknown |
description |
We present a novel Bayesian method, referred to as BLOBBY3D, to infer gas kinematics that mitigates the effects of beam smearing for observations using integral field spectroscopy. The method is robust for regularly rotating galaxies despite substructure in the gas distribution. Modelling the gas substructure within the disc is achieved by using a hierarchical Gaussian mixture model. To account for beam smearing effects, we construct a modelled cube that is then convolved per wavelength slice by the seeing, before calculating the likelihood function. We show that our method can model complex gas substructure including clumps and spiral arms. We also show that kinematic asymmetries can be observed after beam smearing for regularly rotating galaxies with asymmetries only introduced in the spatial distribution of the gas. We present findings for our method applied to a sample of 20 star-forming galaxies from the SAMI Galaxy Survey. We estimate the global H α gas velocity dispersion for our sample to be in the range σ¯v ∼[7, 30] km s−1. The relative difference between our approach and estimates using the single Gaussian component fits per spaxel is σ¯v/σ¯v = −0.29 ± 0.18 for the H α flux-weighted mean velocity dispersion. |
author2 |
Swinburne University of Technology |
format |
Article in Journal/Newspaper |
author |
Varidel, Mathew R. Croom, Scott M. Lewis, Geraint F. Brewer, Brendon J. Di Teodoro, Enrico M. Bland-Hawthorn, Joss Bryant, Julia J. Federrath, Christoph Foster, Caroline Glazebrook, Karl Goodwin, Michael Groves, Brent Hopkins, Andrew M. Lawrence, Jon S. Lopez-Ssnchez, Angel R. Medling, Anne M. Owers, Matt S. Richards, Samuel N. Scalzo, Richard Scott, Nicholas Sweet, Sarah M. Taranu, Dan S. van de Sande, Jesse |
spellingShingle |
Varidel, Mathew R. Croom, Scott M. Lewis, Geraint F. Brewer, Brendon J. Di Teodoro, Enrico M. Bland-Hawthorn, Joss Bryant, Julia J. Federrath, Christoph Foster, Caroline Glazebrook, Karl Goodwin, Michael Groves, Brent Hopkins, Andrew M. Lawrence, Jon S. Lopez-Ssnchez, Angel R. Medling, Anne M. Owers, Matt S. Richards, Samuel N. Scalzo, Richard Scott, Nicholas Sweet, Sarah M. Taranu, Dan S. van de Sande, Jesse The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
author_facet |
Varidel, Mathew R. Croom, Scott M. Lewis, Geraint F. Brewer, Brendon J. Di Teodoro, Enrico M. Bland-Hawthorn, Joss Bryant, Julia J. Federrath, Christoph Foster, Caroline Glazebrook, Karl Goodwin, Michael Groves, Brent Hopkins, Andrew M. Lawrence, Jon S. Lopez-Ssnchez, Angel R. Medling, Anne M. Owers, Matt S. Richards, Samuel N. Scalzo, Richard Scott, Nicholas Sweet, Sarah M. Taranu, Dan S. van de Sande, Jesse |
author_sort |
Varidel, Mathew R. |
title |
The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
title_short |
The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
title_full |
The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
title_fullStr |
The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
title_full_unstemmed |
The SAMI Galaxy Survey: Bayesian inference for gas disc kinematics using a hierarchical Gaussian mixture model |
title_sort |
sami galaxy survey: bayesian inference for gas disc kinematics using a hierarchical gaussian mixture model |
publisher |
Oxford University Press (OUP) |
publishDate |
2019 |
url |
http://hdl.handle.net/1959.3/450023 https://doi.org/10.1093/mnras/stz670 |
genre |
sami |
genre_facet |
sami |
op_source |
Monthly Notices of the Royal Astronomical Society, Vol. 485, no. 3 (May 2019), pp. 4024-4044 |
op_relation |
http://purl.org/au-research/grants/arc/CE170100013 http://purl.org/au-research/grants/arc/CE110001020 http://purl.org/au-research/grants/arc/DP160100723 http://purl.org/au-research/grants/arc/FT180100231 http://purl.org/au-research/grants/arc/DP170100603 http://purl.org/au-research/grants/arc/FT180100495 http://purl.org/au-research/grants/arc/FT140101202 http://purl.org/au-research/grants/arc/FT140100255 http://hdl.handle.net/1959.3/450023 https://doi.org/10.1093/mnras/stz670 |
op_rights |
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. Copyright © 2019 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
op_doi |
https://doi.org/10.1093/mnras/stz670 |
container_title |
Monthly Notices of the Royal Astronomical Society |
container_volume |
485 |
container_issue |
3 |
container_start_page |
4024 |
op_container_end_page |
4044 |
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1766184235310252032 |