Stellar populations of kinematically decoupled cores in E/S0 galaxies
In this poster contribution, we present results from high spatial resolution integral-field spectroscopy of elliptical (E) and lenticular (S0) galaxies from the SAURON representative survey, obtained with the OASIS and GMOS spectrographs. These seeing-limited observations explore the central 10'...
| Main Authors: | , , , , , , , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
2006
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| _version_ | 1797072941231374336 |
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| author | McDermid, R Emsellem, E Shapiro, K Bacon, R Bureau, M Cappellari, M Davies, R De Zeeuw, T Falcón-Barroso, J Krajnovíc, D Kuntschner, H Peletier, R Sarzi, M |
| author_facet | McDermid, R Emsellem, E Shapiro, K Bacon, R Bureau, M Cappellari, M Davies, R De Zeeuw, T Falcón-Barroso, J Krajnovíc, D Kuntschner, H Peletier, R Sarzi, M |
| author_sort | McDermid, R |
| collection | OXFORD |
| description | In this poster contribution, we present results from high spatial resolution integral-field spectroscopy of elliptical (E) and lenticular (S0) galaxies from the SAURON representative survey, obtained with the OASIS and GMOS spectrographs. These seeing-limited observations explore the central 10'10 (typically one kiloparsec diameter) regions of these galaxies using a spatial sampling four times higher than SAURON (027 vs. 094 spatial elements), resulting in almost a factor of two improvement in the median PSF. These data allow accurate study of the central regions to complement the large-scale view provided by SAURON. We derive the stellar and gas kinematics, stellar absorption-line strengths and nebular emission-line strengths for our sample, and derive maps of the luminosity-weighted stellar age, metallicity and abundance ratio via stellar population models. From these data we find a wealth of structures either not seen or poorly resolved in the SAURON data, including a number of kinematically-decoupled cores (KDCs) in the centres of some galaxies. We compare the intrinsic size and luminosity-weighted stellar age of all the visible KDCs in the full SAURON sample, and find two types of components: kiloparsec-scale KDCs, which are older than 8 Gyr, and are found in galaxies with little net rotation; and compact KDCs, which have intrinsic diameters of less than a few hundred parsec, show a range of stellar ages from 0.5 - 15 Gyr (with 5/6 younger than 5 Gyr), are found exclusively in fast-rotating galaxies, and are close to counter-rotating around the same axis as their host. Of the 7 galaxies in the SAURON sample with integrated luminosity-weighted ages less than 5 Gyr, 5 show such compact KDCs, suggesting a link between counter-rotation and recent star-formation. We show that this may be partly due to a combination of small sample size at young ages, and an observational bias, since young KDCs are easier to detect than their older and/or co-rot ating counterparts. |
| first_indexed | 2024-03-06T23:14:55Z |
| format | Journal article |
| id | oxford-uuid:66cd3602-64f9-422f-a675-02a730a6bf84 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T23:14:55Z |
| publishDate | 2006 |
| record_format | dspace |
| spelling | oxford-uuid:66cd3602-64f9-422f-a675-02a730a6bf842022-03-26T18:34:10ZStellar populations of kinematically decoupled cores in E/S0 galaxiesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:66cd3602-64f9-422f-a675-02a730a6bf84EnglishSymplectic Elements at Oxford2006McDermid, REmsellem, EShapiro, KBacon, RBureau, MCappellari, MDavies, RDe Zeeuw, TFalcón-Barroso, JKrajnovíc, DKuntschner, HPeletier, RSarzi, MIn this poster contribution, we present results from high spatial resolution integral-field spectroscopy of elliptical (E) and lenticular (S0) galaxies from the SAURON representative survey, obtained with the OASIS and GMOS spectrographs. These seeing-limited observations explore the central 10'10 (typically one kiloparsec diameter) regions of these galaxies using a spatial sampling four times higher than SAURON (027 vs. 094 spatial elements), resulting in almost a factor of two improvement in the median PSF. These data allow accurate study of the central regions to complement the large-scale view provided by SAURON. We derive the stellar and gas kinematics, stellar absorption-line strengths and nebular emission-line strengths for our sample, and derive maps of the luminosity-weighted stellar age, metallicity and abundance ratio via stellar population models. From these data we find a wealth of structures either not seen or poorly resolved in the SAURON data, including a number of kinematically-decoupled cores (KDCs) in the centres of some galaxies. We compare the intrinsic size and luminosity-weighted stellar age of all the visible KDCs in the full SAURON sample, and find two types of components: kiloparsec-scale KDCs, which are older than 8 Gyr, and are found in galaxies with little net rotation; and compact KDCs, which have intrinsic diameters of less than a few hundred parsec, show a range of stellar ages from 0.5 - 15 Gyr (with 5/6 younger than 5 Gyr), are found exclusively in fast-rotating galaxies, and are close to counter-rotating around the same axis as their host. Of the 7 galaxies in the SAURON sample with integrated luminosity-weighted ages less than 5 Gyr, 5 show such compact KDCs, suggesting a link between counter-rotation and recent star-formation. We show that this may be partly due to a combination of small sample size at young ages, and an observational bias, since young KDCs are easier to detect than their older and/or co-rot ating counterparts. |
| spellingShingle | McDermid, R Emsellem, E Shapiro, K Bacon, R Bureau, M Cappellari, M Davies, R De Zeeuw, T Falcón-Barroso, J Krajnovíc, D Kuntschner, H Peletier, R Sarzi, M Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title | Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title_full | Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title_fullStr | Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title_full_unstemmed | Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title_short | Stellar populations of kinematically decoupled cores in E/S0 galaxies |
| title_sort | stellar populations of kinematically decoupled cores in e s0 galaxies |
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