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arXiv · 0911.3111

The 400d Galaxy Cluster Survey Weak Lensing Programme: I: MMT/Megacam Analysis of CL0030+2618 at z=0.50

Holger Israel·Thomas Erben·Thomas H. Reiprich·Alexey Vikhlinin·Hendrik Hildebrandt·Daniel S. Hudson·Brian A. McLeod·Craig L. Sarazin·Peter Schneider·Yu-Ying Zhang
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Abstract

The mass function of galaxy clusters at high redshifts is a particularly useful probe to learn about the history of structure formation and constrain cosmological parameters. We aim at deriving reliable masses for a high-redshift, high-luminosity sample of clusters of galaxies selected from the 400d survey of X-ray selected clusters. Here, we will focus on a particular object, CL0030+2618 at z=0.50 Using deep imaging in three passbands with the MEGACAM instrument at MMT, we show that MEGACAM is well-suited for measuring gravitational shear. We detect the weak lensing signal of CL0030+2618 at 5.8 sigma significance, using the aperture mass technique. Furthermore, we find significant tangential alignment of galaxies out to ~10 arcmin or >2r_200 distance from the cluster centre. The weak lensing centre of CL0030+2618 agrees with several X-ray measurements and the position of the brightest cluster galaxy. Finally, we infer a weak lensing virial mass of M_200=7.5 10^{14} M_sun for CL0030+2618. Despite complications by a tentative foreground galaxy group in the line of sight, the X-ray and weak lensing estimates for CL0030+2618 are in remarkable agreement. This study paves the way for the largest weak lensing survey of high-redshift galaxy clusters to date.

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Holger Israel, Thomas Erben, Thomas H. Reiprich, Alexey Vikhlinin, Hendrik Hildebrandt, Daniel S. Hudson, Brian A. McLeod, Craig L. Sarazin, Peter Schneider, Yu-Ying Zhang. 2009-11-16. The 400d Galaxy Cluster Survey Weak Lensing Programme: I: MMT/Megacam Analysis of CL0030+2618 at z=0.50. https://doi.org/10.1051/0004-6361/200913667

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