Non-spherical similarity solutions for dark halo formation
نویسندگان
چکیده
منابع مشابه
Halo Formation in Warm Dark Matter Models
Discrepancies have emerged between the predictions of standard cold dark matter (CDM) theory and observations of clustering on sub-galactic scales. Warm dark matter (WDM) is a simple modification of CDM in which the dark matter particles have initial velocities due either to their having decoupled as thermal relics, or having been formed via non-equilibrium decay. We investigate the nonlinear g...
متن کاملIs the dark halo of our Galaxy spherical ?
It has been recently claimed that the confined structure of the debris from the Sagittarius dwarf implies that the dark-matter halo of our Galaxy should be nearly spherical, in strong contrast with predictions from cold dark-matter (CDM) simulations, where dark halos are found to have typical density axis ratios of 0.6− 0.8. In this letter, numerical simulations are used to show that the Sagitt...
متن کاملDark Matter Halo Environment for Primordial Star Formation
We study the statistical properties (such as shape and spin) of high-z halos likely hosting the first (PopIII) stars with cosmological simulations including detailed gas physics. In the redshift range considered (11 < z < 16) the average sphericity is 〈s〉 = 0.3 ± 0.1, and for more than 90% of halos the triaxiality parameter is T . 0.4, showing a clear preference for oblateness over prolateness....
متن کاملThe statistical properties of Λ cold dark matter halo formation
We present a comparison of the statistical properties of dark matter halo merger trees extracted from the Millennium Simulation with Extended Press–Schechter (EPS) formalism and the related GALFORM Monte Carlo method for generating ensembles of merger trees. The volume, mass resolution and output frequency make the Millennium Simulation a unique resource for the study of the hierarchical growth...
متن کاملEnvironmental Dependence of Cold Dark Matter Halo Formation
We use a high-resolution N -body simulation to study how the formation of cold dark matter (CDM) halos is affected by their environments, and how such environmental effects produce the age-dependence of halo clustering observed in recent N -body simulations. We estimate, for each halo selected at redshift z = 0, an ‘initial’ massMi defined to be the mass enclosed by the largest sphere which con...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2011
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2011.18605.x