LoCuSS: THE SUNYAEV–ZEL’DOVICH EFFECT AND WEAK-LENSING MASS SCALING RELATION
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Marrone, Daniel P.
Smith, Graham P.
Carlstrom, John E.
Culverhouse, Thomas L.
Greer, Christopher H.
Lamb, James W.
Leitch, Erik M.
Sanderson, Alastair J. R.
cosmology: observations – galaxies: clusters: intracluster medium – gravitational lensing: weak
We present the firstweak-lensing-based scaling relation between galaxy clustermass,MWL, and integrated Compton parameter Ysph. Observations of 18 galaxy clusters at z ≃ 0.2 were obtained with the Subaru 8.2 m telescope and the Sunyaev–Zel’dovich Array. The MWL–Ysph scaling relations, measured at Δ = 500, 1000, and 2500 ρc, are consistent in slope and normalization with previous results derived under the assumption of hydrostatic equilibrium (HSE). We find an intrinsic scatter in MWL at fixed Ysph of 20%, larger than both previous measurements of MHSE–Ysph scatter as well as the scatter in true mass at fixed Ysph found in simulations. Moreover, the scatter in our lensing-based scaling relations is morphology dependent, with 30%–40% larger MWL for undisturbed compared to disturbed clusters at the same Ysph at r500. Further examination suggests that the segregation may be explained by the inability of our spherical lens models to faithfully describe the three-dimensional structure of the clusters, in particular, the structure along the line of sight.We find that the ellipticity of the brightest cluster galaxy, a proxy for halo orientation, correlates well with the offset in mass from the mean scaling relation, which supports this picture. This provides empirical evidence that line-of-sight projection effects are an important systematic uncertainty in lensing-based scaling relations.
Support for CARMA construction was derived from the Gordon and Betty Moore Foundation, the Kenneth T. and Eileen L. Norris Foundation, the James S. McDonnell Foundation, the Associates of the California Institute of Technology, the University of Chicago, the states of California, Illinois, and Maryland, and the National Science Foundation. Ongoing CARMA development and operations are supported by the National Science Foundation under a cooperative agreement, including grant AST-0838187 at the University of Chicago, and by the CARMA partner universities. Partial support is provided by NSF Physics Frontier Center Grant PHY-0114422 to the Kavli Institute of Cosmological Physics. D. P. M. was supported for part of this work by NASA through Hubble Fellowship Grant HST-HF-51259.01. He acknowledges the Kavli Institute for Theoretical Physics for its hospitality during part of this research, supported by NSF Grant PHY-0551164. G. P. S. acknowledges support from the Royal Society. Support for T. M. was provided by NASA through the Einstein Fellowship Program, grant PF0-110077. N. O. was partially supported by a Grant-in-Aid (0740099), and this work was supported by the programs “Weaving Science Web beyond Particle-Matter Hierarchy” in Tohoku University and “Probing the Dark Energy through an Extremely Wide and Deep Survey with Subaru Telescope” (18072001), all of which are funded by theMinistry of Education, Culture, Sports, Science, and Technology of Japan.Y.Y.Z. acknowledges support from the German BMBF through the Verbundforschung under grant No. 50 OR 1005.
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