Abundance and evolution of galaxy clusters in cosmological models with massive neutrino
نویسندگان
چکیده
An abstract should be given The time evolution of the number density of galaxy clusters and their mass and temperature functions are used to constrain cosmological parameters in the spatially flat dark matter models containing a fraction of hot particles (massive neutrino) additional to cold and baryonic matter. We test the modified MDM models with cosmic gravitational waves and show that they neither pass the cluster evolution test nor reproduce the observed height of the first acoustic peak in ∆T/T spectrum, and therefore should be ruled out. The models with a non-zero cosmological constant are in better agreement with the observations. We estimate the free cosmological parameters in ΛMDM with a negligible abundance of gravitational waves, and find that within the parameter ranges fν ≡ Ων/Ωm ∈ (0, 0.2), h ∈ (0.6, 0.7), and n ∈ (0.9, 1.1), (i) ΩΛ is strongly affected by a small fraction of hot matter, 0.45 < ΩΛ < 0.7 (1σ CL), and (ii) the cluster evolution test alone reveals the following explicit correlation between ΩΛ and fν : ΩΛ + 0.5fν = 0.65± 0.1.
منابع مشابه
Evolution of Galaxy Clusters in Λmdm Cosmologies
The time evolution of galaxy cluster abundance is used to constrain cosmological parameters in dark matter models containing a fraction of hot particles (massive neutrino). We test the modified MDM models with cosmic gravitational waves which are in agreement with observational data at z = 0, and show that they do not pass the cluster evolution test and therefore should be ruled out. The models...
متن کاملاندازهگیری نمایه عمق نوری خوشههای کهکشانی با استفاده از اثرسونیائف زلدوویچ جنبشی
baryonic matter distribution in the large-scale structures is one of the main questions in cosmology. This distribution can provide valuable information regarding the processes of galaxy formation and evolution. On the other hand, the missing baryon problem is still under debate. One of the most important cosmological structures for studying the rate and the distribution of the baryons is gal...
متن کاملScaling relations in dynamical evolution of star clusters
We have carried out a series of small scale collisional N-body calculations of single-mass star clusters to investigate the dependence of the lifetime of star clusters on their initial parameters. Our models move through an external galaxy potential with a logarithmic density profile and they are limited by a cut-off radius. In order to find scaling relations between the lifetime of star cluste...
متن کاملEvolution of Large Scale Structure { Garching , August 1998 DETERMINING COSMOLOGICAL PARAMETERSFROM CLUSTER
We show that the evolution of the number density of rich clusters of galaxies breaks thèclassical' degeneracy between (the cosmological mass density parameter of the universe) and 8 (The amplitude of mass uc-tuations on 8Mpc scale) that follows from the observed present-day cluster abundance. The evolution of cluster abundance thus provides a determination of each of these parameters independen...
متن کاملPower Spectra for Cold Dark Matter and its Variants
The bulk of recent cosmological research has focused on the adiabatic cold dark matter model and its simple extensions. Here we present an accurate tting formula that describes the matter transfer functions of all common variants, including mixed dark matter models. The result is a function of wavenumber, time, and six cosmological parameters: the massive neutrino density, number of neutrino sp...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2001