Abstract
We compare the combined distribution of 31 group and 25 cluster velocity dispersions [Zabludoff et al., AJ, 106, 1301 (1993)] with the ensemble of 32 models for the formation and evolution of large-scale structure examined by Weinberg & Cole [MNRAS, 259, 652 (1992)]. The models include Gaussian and non-Gaussian initial fluctuations, different power law spectra (n=-1, n=0, n=-2, "pancake"), flat (Ω=1) and open (Ω=0.2) cosmologies, and unbiased (b8=1) and biased (b8=2) galaxy formation. The set of initial conditions we test, although limited, samples enough parameter space to indicate which general classes of models are consistent with the data. The two Gaussian, n=-1 models which best approximate the standard and open Cold Dark Matter (CDM) models do not match the observed distribution of velocity dispersions; models with b8=2 and Ω=1 ("standard") or b8=1 and Ω=0.2 ("open") predict too large a ratio of low to high velocity dispersion systems. A "COBE-normalized" CDM model with b8=1 and Ω=1 produces clusters with velocity dispersions higher than those measured. All three models overestimate the total abundance of systems.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1929-1936 |
| Number of pages | 8 |
| Journal | Astronomical Journal |
| Volume | 107 |
| Issue number | 6 |
| State | Published - Jun 1994 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Space and Planetary Science
- Astronomy and Astrophysics
Cite this
The kinematics of dense clusters of galaxies. III. Comparison with cosmological models. / Zabludoff, Ann I; Geller, Margaret J.
In: Astronomical Journal, Vol. 107, No. 6, 06.1994, p. 1929-1936.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The kinematics of dense clusters of galaxies. III. Comparison with cosmological models
AU - Zabludoff, Ann I
AU - Geller, Margaret J.
PY - 1994/6
Y1 - 1994/6
N2 - We compare the combined distribution of 31 group and 25 cluster velocity dispersions [Zabludoff et al., AJ, 106, 1301 (1993)] with the ensemble of 32 models for the formation and evolution of large-scale structure examined by Weinberg & Cole [MNRAS, 259, 652 (1992)]. The models include Gaussian and non-Gaussian initial fluctuations, different power law spectra (n=-1, n=0, n=-2, "pancake"), flat (Ω=1) and open (Ω=0.2) cosmologies, and unbiased (b8=1) and biased (b8=2) galaxy formation. The set of initial conditions we test, although limited, samples enough parameter space to indicate which general classes of models are consistent with the data. The two Gaussian, n=-1 models which best approximate the standard and open Cold Dark Matter (CDM) models do not match the observed distribution of velocity dispersions; models with b8=2 and Ω=1 ("standard") or b8=1 and Ω=0.2 ("open") predict too large a ratio of low to high velocity dispersion systems. A "COBE-normalized" CDM model with b8=1 and Ω=1 produces clusters with velocity dispersions higher than those measured. All three models overestimate the total abundance of systems.
AB - We compare the combined distribution of 31 group and 25 cluster velocity dispersions [Zabludoff et al., AJ, 106, 1301 (1993)] with the ensemble of 32 models for the formation and evolution of large-scale structure examined by Weinberg & Cole [MNRAS, 259, 652 (1992)]. The models include Gaussian and non-Gaussian initial fluctuations, different power law spectra (n=-1, n=0, n=-2, "pancake"), flat (Ω=1) and open (Ω=0.2) cosmologies, and unbiased (b8=1) and biased (b8=2) galaxy formation. The set of initial conditions we test, although limited, samples enough parameter space to indicate which general classes of models are consistent with the data. The two Gaussian, n=-1 models which best approximate the standard and open Cold Dark Matter (CDM) models do not match the observed distribution of velocity dispersions; models with b8=2 and Ω=1 ("standard") or b8=1 and Ω=0.2 ("open") predict too large a ratio of low to high velocity dispersion systems. A "COBE-normalized" CDM model with b8=1 and Ω=1 produces clusters with velocity dispersions higher than those measured. All three models overestimate the total abundance of systems.
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M3 - Article
AN - SCOPUS:0344671017
VL - 107
SP - 1929
EP - 1936
JO - Astronomical Journal
JF - Astronomical Journal
SN - 0004-6256
IS - 6
ER -