TY - GEN

T1 - Constraining dark energy and modified gravity with galaxy clusters, Oskar Klein Center for Cosmoparticle Physics, Stockholm, Sweden

AU - Rapetti Serra, David Angelo

PY - 2011/9/13

Y1 - 2011/9/13

N2 - Using measurements of the abundance of galaxy clusters weobtain constraints on dark energy and gravity atcosmological scales. Our data set consists of 238 clusterdetections drawn from the ROSAT All-Sky Survey and X-rayfollow-up observations of 94 of those clusters. Using a newstatistical framework we self-consistently andsimultaneously constrain cosmology and observable-massscaling relations accounting for survey biases, parametercovariances and systematic uncertainties. Allowing thelinear growth index and the dark energy equation of state totake any constant values, we find no evidence for departuresfrom GR+LCDM. If time permits, I will also presentpreliminary results on testing an alternative gravity modelusing our cluster data sets. Our results highlight the powerof X-ray cluster studies to constrain cosmology

AB - Using measurements of the abundance of galaxy clusters weobtain constraints on dark energy and gravity atcosmological scales. Our data set consists of 238 clusterdetections drawn from the ROSAT All-Sky Survey and X-rayfollow-up observations of 94 of those clusters. Using a newstatistical framework we self-consistently andsimultaneously constrain cosmology and observable-massscaling relations accounting for survey biases, parametercovariances and systematic uncertainties. Allowing thelinear growth index and the dark energy equation of state totake any constant values, we find no evidence for departuresfrom GR+LCDM. If time permits, I will also presentpreliminary results on testing an alternative gravity modelusing our cluster data sets. Our results highlight the powerof X-ray cluster studies to constrain cosmology

M3 - Other contribution

CY - Stockholm, Sweden

ER -