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arXiv · 1710.06431

Weak lensing magnification of SpARCS galaxy clusters

A. Tudorica·H. Hildebrandt·M. Tewes·H. Hoekstra·C. B. Morrison·A. Muzzin·G. Wilson·H. K. C. Yee·C. Lidman·A. Hicks·J. Nantais·T. Erben·R. F. J. van der Burg·R. Demarco
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Abstract

Measuring and calibrating relations between cluster observables is critical for resource-limited studies. The mass-richness relation of clusters offers an observationally inexpensive way of estimating masses. Its calibration is essential for cluster and cosmological studies, especially for high-redshift clusters. Weak gravitational lensing magnification is a promising and complementary method to shear studies, that can be applied at higher redshifts. We employed the weak lensing magnification method to calibrate the mass-richness relation up to a redshift of 1.4. We used the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS) galaxy cluster candidates ($0.2 1.0$ is 4.1$\sigma$; for the entire cluster sample we obtained an average M$_{200}$ of $1.28^{+0.23}_{-0.21}$ $\times 10^{14} \, \textrm{M}_{\odot}$. Our measurements demonstrated the feasibility of using weak lensing magnification as a viable tool for determining the average halo masses for samples of high redshift galaxy clusters. The results also established the success of using galaxy over-densities to select massive clusters at $z > 1$. Additional studies are necessary for further modelling of the various systematic effects we discussed.

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A. Tudorica, H. Hildebrandt, M. Tewes, H. Hoekstra, C. B. Morrison, A. Muzzin, G. Wilson, H. K. C. Yee, C. Lidman, A. Hicks, J. Nantais, T. Erben, R. F. J. van der Burg, R. Demarco. 2017-10-17. Weak lensing magnification of SpARCS galaxy clusters. https://doi.org/10.1051/0004-6361%2F201731267

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