Astronomy and Astrophysics – Astrophysics
Scientific paper
1994-03-07
Astrophys.J. 432 (1994) 438
Astronomy and Astrophysics
Astrophysics
21 pages + 6 figures (uuencoded version of the PS files), Steward Preprints No. 1184
Scientific paper
10.1086/174582
Using a set of $\pppm$ simulation which accurately treats the density evolution of two components of dark matter, we study the evolution of clusters in the Cold + Hot dark matter (CHDM) model. The mass function, the velocity dispersion function and the temperature function of clusters are calculated for four different epochs of $z\le 0.5$. We also use the simulation data to test the Press-Schechter expression of the halo abundance as a function of the velocity dispersion $\sigma_v$. The model predictions are in good agreement with the observational data of local cluster abundances ($z=0$). We also tentatively compare the model with the Gunn and his collaborators' observation of rich clusters at $z\approx 0.8$ and with the x-ray luminous clusters at $z\approx 0.5$ of the {\it Einstein} Extended Medium Sensitivity Survey. The important feature of the model is the rapid formation of clusters in the near past: the abundances of clusters of $\sigma_v\ge 700\kms$ and of $\sigma_v\ge 1200 \kms$ at $z=0.5$ are only 1/4 and 1/10 respectively of the present values ($z=0$). Ongoing ROSAT and AXAF surveys of distant clusters will provide sensitive tests to the model. The abundance of clusters at $z\approx 0.5$ would also be a good discriminator between the CHDM model and a low-density flat CDM model both of which show very similar clustering properties at $z=0$.
Fang L.-Z.
Jing Yi-Peng
No associations
LandOfFree
Abundance of moderate-redshift clusters in the Cold + Hot dark matter model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Abundance of moderate-redshift clusters in the Cold + Hot dark matter model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Abundance of moderate-redshift clusters in the Cold + Hot dark matter model will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-400229