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تسجيل مستخدم جديدConstraining cosmological parameters using Sunyaev-Zeldovich cluster surveys
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We discuss how future cluster surveys can constrain cosmological parameters with particular reference to the properties of the dark energy component responsible for the observed acceleration of the universe by probing the evolution of the surface density of clusters as a function of redshift. We explain how the abundance of clusters selected using their Sunyaev-Zeldovich effect can be computed as a function of the observed flux and redshift taking into account observational effects due to a finite beam-size. By constructing an idealized set of simulated observations for a fiducial model, we forecast the likely constraints that might be possible for a variety of proposed surveys which are assumed to be flux limited. We find that Sunyaev-Zeldovich cluster surveys can provide vital complementary information to those expected from surveys for supernovae. We analyse the impact of statistical and systematic uncertainties and find that they only slightly limit our ability to constrain the equation of state of the dark energy component.
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We discuss the prospects of constraining the properties of a dark energy component, with particular reference to a time varying equation of state, using future cluster surveys selected by their Sunyaev-Zeldovich effect. We compute the number of clust
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Sunyaev Zeldovich cluster surveys can be used to constrain cosmological parameters. Extracting clusters from the primary anisotropies and the unresolved background from very faint clusters is simple when the telescope beam size is small (1 arcmin), b
ut could be difficult if the beam is larger (8 arcmin). By reference to examples, we show that this is possible by carefully designing the depth of the survey.
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