RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy cluster at z=0.28
We present a photometric and spectroscopic study of stellar populations in the X-ray-luminous cluster of galaxies RXJ0142.0+2131 at z=0.280. This paper analyses the results of high signal-to-noise spectroscopy, as well as g'-, r'-, and i'-band imaging, using the Gemini Multi-Object Sp...
| Main Authors: | , , , , |
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| Format: | Journal article |
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2005
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| _version_ | 1797097310281269248 |
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| author | Barr, J Davies, R Jorgensen, I Bergmann, M Crampton, D |
| author_facet | Barr, J Davies, R Jorgensen, I Bergmann, M Crampton, D |
| author_sort | Barr, J |
| collection | OXFORD |
| description | We present a photometric and spectroscopic study of stellar populations in the X-ray-luminous cluster of galaxies RXJ0142.0+2131 at z=0.280. This paper analyses the results of high signal-to-noise spectroscopy, as well as g'-, r'-, and i'-band imaging, using the Gemini Multi-Object Spectrograph on Gemini North. Of 43 spectroscopic targets, we find 30 cluster members over a range in color. Central velocity dispersions and absorption-line strengths for lines in the range 3700A < lambda_rest < 5800A are derived for cluster members, and are compared with a low-redshift sample of cluster galaxies, and single stellar population (SSP) models. We use a combination of these indicators to estimate luminosity-weighted mean ages, metallicities ([M/H]), and alpha-element abundance ratios ([alpha/Fe]). RXJ0142.0+2131 is a relatively poor cluster and lacks galaxies with high central velocity dispersions. Although the red sequence and the Faber-Jackson relation are consistent with pure passive evolution of the early-type population with a formation redshift of z_form = 2, the strengths of the 4000A break and scaling relations between metal line indices and velocity dispersion reject this model with high significance. By inverting SSP models for the Hbeta_G, Mgb, and <fe> line indices, we calculate that, at a given velocity dispersion and metallicity, galaxies in RXJ0142.0+2131 have luminosity-weighted mean ages 0.14 +- 0.07 dex older than the low-redshift sample. We also find that [alpha/Fe] in stellar populations in RXJ0142.0+2131 is 0.14 +- 0.03 greater than at low redshift. All scaling relations are consistent with these estimated offsets. (abridged)</fe> |
| first_indexed | 2024-03-07T04:53:42Z |
| format | Journal article |
| id | oxford-uuid:d5d9683d-6d10-466e-b7a6-7a8d3ee2b594 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T04:53:42Z |
| publishDate | 2005 |
| record_format | dspace |
| spelling | oxford-uuid:d5d9683d-6d10-466e-b7a6-7a8d3ee2b5942022-03-27T08:29:02ZRXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy cluster at z=0.28Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:d5d9683d-6d10-466e-b7a6-7a8d3ee2b594Symplectic Elements at Oxford2005Barr, JDavies, RJorgensen, IBergmann, MCrampton, DWe present a photometric and spectroscopic study of stellar populations in the X-ray-luminous cluster of galaxies RXJ0142.0+2131 at z=0.280. This paper analyses the results of high signal-to-noise spectroscopy, as well as g'-, r'-, and i'-band imaging, using the Gemini Multi-Object Spectrograph on Gemini North. Of 43 spectroscopic targets, we find 30 cluster members over a range in color. Central velocity dispersions and absorption-line strengths for lines in the range 3700A < lambda_rest < 5800A are derived for cluster members, and are compared with a low-redshift sample of cluster galaxies, and single stellar population (SSP) models. We use a combination of these indicators to estimate luminosity-weighted mean ages, metallicities ([M/H]), and alpha-element abundance ratios ([alpha/Fe]). RXJ0142.0+2131 is a relatively poor cluster and lacks galaxies with high central velocity dispersions. Although the red sequence and the Faber-Jackson relation are consistent with pure passive evolution of the early-type population with a formation redshift of z_form = 2, the strengths of the 4000A break and scaling relations between metal line indices and velocity dispersion reject this model with high significance. By inverting SSP models for the Hbeta_G, Mgb, and <fe> line indices, we calculate that, at a given velocity dispersion and metallicity, galaxies in RXJ0142.0+2131 have luminosity-weighted mean ages 0.14 +- 0.07 dex older than the low-redshift sample. We also find that [alpha/Fe] in stellar populations in RXJ0142.0+2131 is 0.14 +- 0.03 greater than at low redshift. All scaling relations are consistent with these estimated offsets. (abridged)</fe> |
| spellingShingle | Barr, J Davies, R Jorgensen, I Bergmann, M Crampton, D RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy cluster at z=0.28 |
| title | RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy
cluster at z=0.28 |
| title_full | RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy
cluster at z=0.28 |
| title_fullStr | RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy
cluster at z=0.28 |
| title_full_unstemmed | RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy
cluster at z=0.28 |
| title_short | RXJ0142.0+2131: I. The galaxy content of an X-ray-luminous galaxy
cluster at z=0.28 |
| title_sort | rxj0142 0 2131 i the galaxy content of an x ray luminous galaxy cluster at z 0 28 |
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