The SAMI galaxy survey: stellar population radial gradients in early-type galaxies
We study the internal radial gradients of the stellar populations in a sample comprising 522 early-type galaxies (ETGs) from the SAMI (Sydney-AAO Multi-object Integral field spectrograph) Galaxy Survey. We stack the spectra of individual spaxels in radial bins, and derive basic stellar population pr...
Published in: | Monthly Notices of the Royal Astronomical Society |
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Oxford University Press (OUP)
2019
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Online Access: | http://hdl.handle.net/1959.3/461928 https://doi.org/10.1093/mnras/stz2095 |
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ftswinburne:tle:5e9e4f58-5645-4ff0-a8c2-c20e479df682:28f49f06-0da8-44be-9edc-ad1dd0a9c582:1 2023-05-15T18:11:22+02:00 The SAMI galaxy survey: stellar population radial gradients in early-type galaxies Ferreras, Ignacio Scott, Nicholas La Barbera, Francesco Croom, Scott van de Sande, Jesse Hopkins, Andrew Colless, Matthew Barone, Tania M. d’Eugenio, Francesco Bland-Hawthorn, Joss Brough, Sarah Bryant, Julia J. Konstantopoulos, Iraklis S. Lagos, Claudia Lawrence, Jon S. López-Sánchez, Angel Medling, Anne M. Owers, Matt S. Richards, Samuel N. Swinburne University of Technology 2019 http://hdl.handle.net/1959.3/461928 https://doi.org/10.1093/mnras/stz2095 unknown Oxford University Press (OUP) http://hdl.handle.net/1959.3/461928 https://doi.org/10.1093/mnras/stz2095 Copyright © 2019 Monthly Notices of the Royal Astronomical Society, Vol. 489, no. 1 (Oct 2019), pp. 608-622 Journal article 2019 ftswinburne https://doi.org/10.1093/mnras/stz2095 2021-07-26T22:26:31Z We study the internal radial gradients of the stellar populations in a sample comprising 522 early-type galaxies (ETGs) from the SAMI (Sydney-AAO Multi-object Integral field spectrograph) Galaxy Survey. We stack the spectra of individual spaxels in radial bins, and derive basic stellar population properties: total metallicity ([Z/H]), [Mg/Fe], [C/Fe] and age. The radial gradient (∇) and central value of the fits (evaluated at Re/4) are compared against a set of six observables that may act as drivers of the trends. We find that velocity dispersion (σ) - or, equivalently gravitational potential - is the dominant driver of the chemical composition gradients. Surface mass density is also correlated with the trends, especially with stellar age. The decrease of ∇[Mg/Fe] with increasing σ is contrasted by a rather shallow dependence of ∇[Z/H] with σ (although this radial gradient is overall rather steep). This result, along with a shallow age slope at the massive end, imposes a substantial constraint on the progenitors of the populations that contribute to the formation of the outer envelopes of ETGs. The SAMI sample is split, by design, between 'field' and cluster galaxies. Only weak environment-related differences are found, most notably a stronger dependence of central total metallicity ([Z/H]e4) with σ, along with a marginal trend of ∇[Z/H] to steepen in cluster galaxies, a result that is not followed by [Mg/Fe]. The results presented here serve as stringent constraints on numerical models of the formation and evolution of ETGs. Article in Journal/Newspaper sami Swinburne University of Technology: Swinburne Research Bank Monthly Notices of the Royal Astronomical Society 489 1 608 622 |
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Open Polar |
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Swinburne University of Technology: Swinburne Research Bank |
op_collection_id |
ftswinburne |
language |
unknown |
description |
We study the internal radial gradients of the stellar populations in a sample comprising 522 early-type galaxies (ETGs) from the SAMI (Sydney-AAO Multi-object Integral field spectrograph) Galaxy Survey. We stack the spectra of individual spaxels in radial bins, and derive basic stellar population properties: total metallicity ([Z/H]), [Mg/Fe], [C/Fe] and age. The radial gradient (∇) and central value of the fits (evaluated at Re/4) are compared against a set of six observables that may act as drivers of the trends. We find that velocity dispersion (σ) - or, equivalently gravitational potential - is the dominant driver of the chemical composition gradients. Surface mass density is also correlated with the trends, especially with stellar age. The decrease of ∇[Mg/Fe] with increasing σ is contrasted by a rather shallow dependence of ∇[Z/H] with σ (although this radial gradient is overall rather steep). This result, along with a shallow age slope at the massive end, imposes a substantial constraint on the progenitors of the populations that contribute to the formation of the outer envelopes of ETGs. The SAMI sample is split, by design, between 'field' and cluster galaxies. Only weak environment-related differences are found, most notably a stronger dependence of central total metallicity ([Z/H]e4) with σ, along with a marginal trend of ∇[Z/H] to steepen in cluster galaxies, a result that is not followed by [Mg/Fe]. The results presented here serve as stringent constraints on numerical models of the formation and evolution of ETGs. |
author2 |
Swinburne University of Technology |
format |
Article in Journal/Newspaper |
author |
Ferreras, Ignacio Scott, Nicholas La Barbera, Francesco Croom, Scott van de Sande, Jesse Hopkins, Andrew Colless, Matthew Barone, Tania M. d’Eugenio, Francesco Bland-Hawthorn, Joss Brough, Sarah Bryant, Julia J. Konstantopoulos, Iraklis S. Lagos, Claudia Lawrence, Jon S. López-Sánchez, Angel Medling, Anne M. Owers, Matt S. Richards, Samuel N. |
spellingShingle |
Ferreras, Ignacio Scott, Nicholas La Barbera, Francesco Croom, Scott van de Sande, Jesse Hopkins, Andrew Colless, Matthew Barone, Tania M. d’Eugenio, Francesco Bland-Hawthorn, Joss Brough, Sarah Bryant, Julia J. Konstantopoulos, Iraklis S. Lagos, Claudia Lawrence, Jon S. López-Sánchez, Angel Medling, Anne M. Owers, Matt S. Richards, Samuel N. The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
author_facet |
Ferreras, Ignacio Scott, Nicholas La Barbera, Francesco Croom, Scott van de Sande, Jesse Hopkins, Andrew Colless, Matthew Barone, Tania M. d’Eugenio, Francesco Bland-Hawthorn, Joss Brough, Sarah Bryant, Julia J. Konstantopoulos, Iraklis S. Lagos, Claudia Lawrence, Jon S. López-Sánchez, Angel Medling, Anne M. Owers, Matt S. Richards, Samuel N. |
author_sort |
Ferreras, Ignacio |
title |
The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
title_short |
The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
title_full |
The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
title_fullStr |
The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
title_full_unstemmed |
The SAMI galaxy survey: stellar population radial gradients in early-type galaxies |
title_sort |
sami galaxy survey: stellar population radial gradients in early-type galaxies |
publisher |
Oxford University Press (OUP) |
publishDate |
2019 |
url |
http://hdl.handle.net/1959.3/461928 https://doi.org/10.1093/mnras/stz2095 |
genre |
sami |
genre_facet |
sami |
op_source |
Monthly Notices of the Royal Astronomical Society, Vol. 489, no. 1 (Oct 2019), pp. 608-622 |
op_relation |
http://hdl.handle.net/1959.3/461928 https://doi.org/10.1093/mnras/stz2095 |
op_rights |
Copyright © 2019 |
op_doi |
https://doi.org/10.1093/mnras/stz2095 |
container_title |
Monthly Notices of the Royal Astronomical Society |
container_volume |
489 |
container_issue |
1 |
container_start_page |
608 |
op_container_end_page |
622 |
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1766184031129436160 |