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...
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Online Access: | https://doi.org/10.1093/mnras/stz2095 https://hdl.handle.net/1959.7/uws:66832 |
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ftunivwestsyd:oai:researchdirect.westernsydney.edu.au:uws_66832 2023-05-15T18:11:21+02:00 The SAMI galaxy survey: Stellar population radial gradients in early-type galaxies Ferreras, I. Scott, N. La Barbera, F. Croom, S. van de Sande, J. Hopkins, Andrew M. (R20610) Colless, M. Barone, T. M. d'Eugenio, F. Bland-Hawthorn, J. Brough, S. Bryant, J. J. Konstantopoulos, I. S. Lagos, C. Lawrence, J. S. López-Sánchez, A. Medling, A. M. Owers, M. S. Richards, S. N. 2019 print 15 https://doi.org/10.1093/mnras/stz2095 https://hdl.handle.net/1959.7/uws:66832 eng eng U.K., Oxford University Press Monthly Notices of the Royal Astronomical Society--0035-8711--1365-2966 Vol. 489 Issue. 1 No. pp: 608-622 XXXXXX - Unknown journal article 2019 ftunivwestsyd https://doi.org/10.1093/mnras/stz2095 2022-08-22T22:25:05Z 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 University of Western Sydney (UWS): Research Direct Monthly Notices of the Royal Astronomical Society 489 1 608 622 |
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University of Western Sydney (UWS): Research Direct |
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ftunivwestsyd |
language |
English |
topic |
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spellingShingle |
XXXXXX - Unknown Ferreras, I. Scott, N. La Barbera, F. Croom, S. van de Sande, J. Hopkins, Andrew M. (R20610) Colless, M. Barone, T. M. d'Eugenio, F. Bland-Hawthorn, J. Brough, S. Bryant, J. J. Konstantopoulos, I. S. Lagos, C. Lawrence, J. S. López-Sánchez, A. Medling, A. M. Owers, M. S. Richards, S. N. The SAMI galaxy survey: Stellar population radial gradients in early-type galaxies |
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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. |
format |
Article in Journal/Newspaper |
author |
Ferreras, I. Scott, N. La Barbera, F. Croom, S. van de Sande, J. Hopkins, Andrew M. (R20610) Colless, M. Barone, T. M. d'Eugenio, F. Bland-Hawthorn, J. Brough, S. Bryant, J. J. Konstantopoulos, I. S. Lagos, C. Lawrence, J. S. López-Sánchez, A. Medling, A. M. Owers, M. S. Richards, S. N. |
author_facet |
Ferreras, I. Scott, N. La Barbera, F. Croom, S. van de Sande, J. Hopkins, Andrew M. (R20610) Colless, M. Barone, T. M. d'Eugenio, F. Bland-Hawthorn, J. Brough, S. Bryant, J. J. Konstantopoulos, I. S. Lagos, C. Lawrence, J. S. López-Sánchez, A. Medling, A. M. Owers, M. S. Richards, S. N. |
author_sort |
Ferreras, I. |
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 |
U.K., Oxford University Press |
publishDate |
2019 |
url |
https://doi.org/10.1093/mnras/stz2095 https://hdl.handle.net/1959.7/uws:66832 |
genre |
sami |
genre_facet |
sami |
op_relation |
Monthly Notices of the Royal Astronomical Society--0035-8711--1365-2966 Vol. 489 Issue. 1 No. pp: 608-622 |
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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1766184030680645632 |