Massive elliptical galaxies : From cores to haloes
In the context of recent observational results that show massive ellipticals were in place at high redshifts, we reassess the status of monolithic collapse in a LCDM universe. Using a sample of over 2000 galaxies from the Sloan Digital Sky Survey, by comparing the dynamical mass and stellar mass (es...
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Format: | Journal article |
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2005
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author | Lintott, C Ferreras, I Lahav, O |
author_facet | Lintott, C Ferreras, I Lahav, O |
author_sort | Lintott, C |
collection | OXFORD |
description | In the context of recent observational results that show massive ellipticals were in place at high redshifts, we reassess the status of monolithic collapse in a LCDM universe. Using a sample of over 2000 galaxies from the Sloan Digital Sky Survey, by comparing the dynamical mass and stellar mass (estimated from colours) we find that ellipticals have `cores' which are baryon-dominated within their half-light radius. These galaxies correspond to 3-sigma peaks in the spherical collapse model if the total mass in the halo is assumed to be 20 times the dynamical mass within the half-light radius. This value yields stellar mass to total mass ratios of 8%, compared to a cosmological baryon fraction of 18% derived from WMAP3 alone. We further develop a method for reconstructing the concentration halo parameter c of the progenitors of these galaxies by utilizing adiabatic contraction. Although the analysis is done within the framework of monolithic collapse, the resulting distribution of c is log-normal with a peak value of c~3-10 and a distribution width similar to the results of N-body simulations. We also derive scaling relations between stellar and dynamical mass and the velocity dispersion, and find that these are sufficient to recover the tilt of the fundamental plane. |
first_indexed | 2024-03-07T04:34:57Z |
format | Journal article |
id | oxford-uuid:cf9dd836-bc05-435b-8d77-ed369e467bbc |
institution | University of Oxford |
last_indexed | 2024-03-07T04:34:57Z |
publishDate | 2005 |
record_format | dspace |
spelling | oxford-uuid:cf9dd836-bc05-435b-8d77-ed369e467bbc2022-03-27T07:43:54ZMassive elliptical galaxies : From cores to haloesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:cf9dd836-bc05-435b-8d77-ed369e467bbcSymplectic Elements at Oxford2005Lintott, CFerreras, ILahav, OIn the context of recent observational results that show massive ellipticals were in place at high redshifts, we reassess the status of monolithic collapse in a LCDM universe. Using a sample of over 2000 galaxies from the Sloan Digital Sky Survey, by comparing the dynamical mass and stellar mass (estimated from colours) we find that ellipticals have `cores' which are baryon-dominated within their half-light radius. These galaxies correspond to 3-sigma peaks in the spherical collapse model if the total mass in the halo is assumed to be 20 times the dynamical mass within the half-light radius. This value yields stellar mass to total mass ratios of 8%, compared to a cosmological baryon fraction of 18% derived from WMAP3 alone. We further develop a method for reconstructing the concentration halo parameter c of the progenitors of these galaxies by utilizing adiabatic contraction. Although the analysis is done within the framework of monolithic collapse, the resulting distribution of c is log-normal with a peak value of c~3-10 and a distribution width similar to the results of N-body simulations. We also derive scaling relations between stellar and dynamical mass and the velocity dispersion, and find that these are sufficient to recover the tilt of the fundamental plane. |
spellingShingle | Lintott, C Ferreras, I Lahav, O Massive elliptical galaxies : From cores to haloes |
title | Massive elliptical galaxies : From cores to haloes |
title_full | Massive elliptical galaxies : From cores to haloes |
title_fullStr | Massive elliptical galaxies : From cores to haloes |
title_full_unstemmed | Massive elliptical galaxies : From cores to haloes |
title_short | Massive elliptical galaxies : From cores to haloes |
title_sort | massive elliptical galaxies from cores to haloes |
work_keys_str_mv | AT lintottc massiveellipticalgalaxiesfromcorestohaloes AT ferrerasi massiveellipticalgalaxiesfromcorestohaloes AT lahavo massiveellipticalgalaxiesfromcorestohaloes |