Biases in the estimation of velocity dispersions and dynamical masses for galaxy clusters
arXiv:1911.03184 · doi:10.1051/epjconf/202022800011
Abstract
Using a set of 73 numerically simulated galaxy clusters, we have characterised the statistical and physical biases for three velocity dispersion and mass estimators, namely biweight, gapper and standard deviation, in the small number of galaxies regime (), both for the determination of the velocity dispersion and the dynamical mass of the clusters via the relation. These results are used to define a new set of unbiased estimators, that are able to correct for those statistical biases. By applying these new estimators to a subset of simulated observations, we show that they can retrieve bias-corrected values for both the mean velocity dispersion and the mean mass.
arXiv comment6 pages, 7 figures, to appear in the proceedings of the international conference entitled mm Universe @ NIKA2, Grenoble (France), June 2019, EPJ Web of conferences
References in corpus (9)
- Virial Scaling of Massive Dark Matter Halos: Why Clusters Prefer a High Normalization Cosmology
- The galaxy cluster mass scale and its impact on cosmological constraints from the cluster population
- The relation between velocity dispersion and mass in simulated clusters of galaxies: dependence on the tracer and the baryonic physics
- Toward Unbiased Galaxy Cluster Masses from Line of Sight Velocity Dispersions
- Optical Spectroscopy and Velocity Dispersions of Galaxy Clusters from the SPT-SZ Survey
- The universal distribution of halo interlopers in projected phase space. Bias in galaxy cluster concentration and velocity anisotropy?
- The Atacama Cosmology Telescope: Dynamical masses for 44 SZ-selected galaxy clusters over 755 square degrees
- Planck Intermediate Results. XXXVI. Optical identification and redshifts of Planck SZ sources with telescopes in the Canary Islands Observatories
- Calibrating the Planck Cluster Mass Scale with Cluster Velocity Dispersions