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We present a detection of the enhancement in the number densities of background galaxies induced from lensing magnification and use it to test the Sunyaev-Zeldovich effect (SZE) inferred masses in a sample of 19 galaxy clusters with median redshift $zsimeq0.42$ selected from the South Pole Telescope SPT-SZ survey. Two background galaxy populations are selected for this study through their photometric colours; they have median redshifts ${z}_{mathrm{median}}simeq0.9$ (low-$z$ background) and ${z}_{mathrm{median}}simeq1.8$ (high-$z$ background). Stacking these populations, we detect the magnification bias effect at $3.3sigma$ and $1.3sigma$ for the low- and high-$z$ backgrounds, respectively. We fit NFW models simultaneously to all observed magnification bias profiles to estimate the multiplicative factor $eta$ that describes the ratio of the weak lensing mass to the mass inferred from the SZE observable-mass relation. We further quantify systematic uncertainties in $eta$ resulting from the photometric noise and bias, the cluster galaxy contamination and the estimations of the background properties. The resulting $eta$ for the combined background populations with $1sigma$ uncertainties is $0.83pm0.24mathrm{(stat)}pm0.074mathrm{(sys)}$, indicating good consistency between the lensing and the SZE-inferred masses. We use our best-fit $eta$ to predict the weak lensing shear profiles and compare these predictions with observations, showing agreement between the magnification and shear mass constraints. This work demonstrates the promise of using the magnification as a complementary method to estimate cluster masses in large surveys.
A clean measurement of the evolution of the galaxy cluster mass function can significantly improve our understanding of cosmology from the rapid growth of cluster masses below z < 0.5. Here we examine the consistency of cluster catalogues selected fr
We propose a novel method to detect cosmic magnification signals by cross-correlating foreground convergence fields constructed from galaxy shear measurements with background galaxy positional distributions, namely shear-number density correlation. W
Dust emission at sub-millimetre wavelengths allows us to trace the early phases of star formation in the Universe. In order to understand the physical processes involved in this mode of star formation, it is essential to gain knowledge about the dark
The magnification effect of gravitational lensing is a powerful probe of the distribution of matter in the universe, yet it is frequently overlooked due to the fact that its signal to noise is smaller than that of lensing shear. Because its systemati
We present a joint shear-and-magnification weak-lensing analysis of a sample of 16 X-ray-regular and 4 high-magnification galaxy clusters at 0.19<z<0.69 selected from the Cluster Lensing And Supernova survey with Hubble (CLASH). Our analysis uses wid