سال انتشار: ۱۳۸۷

محل انتشار: دومین همایش ملی گرانش و کیهان شناسی

تعداد صفحات: ۱

نویسنده(ها):

Habib Khosroshahi – School of astronomy,IPM.tehran

چکیده:

Fossil galaxy groups and clusters are thought to have formed relatively early and hence expected to have preserved crucial information that would otherwise be jost in the hierarchical destruction . I will introduce fossil systems and present evidences to show that they are different from non-fossil systems in their evolutionary history, using both observations and simulations.Observational studies are based on combined optical and X-ray observation including photometric and spectroscopic measurements.These studies show various systematic differences compared to non-fossil systems in their dominat galaxy properties and dark matter content of the derived from X-ray emissions of the inter-galactic medium allawing the probe of modela of galaxy and structure formation . High mass concentration of the fossil halos,the correlation of halo sub-structure fraction and galaxy luminosity gap , as well as thenin – boxy nature of the central galaxy isophotes in fossils.We use this constraints to test the available semi-analytic models of galaxy formation and study halo mass evolution of the fossils and non-fossil systems.