LoCuSS: THE SUNYAEV-ZEL'DOVICH EFFECT AND WEAK-LENSING MASS SCALING RELATION
LoCuSS: THE SUNYAEV-ZEL'DOVICH EFFECT AND WEAK-LENSING MASS SCALING RELATION
复制标题
LoCuSS：SUNYAEV-ZELDOVICH 效应和弱透镜质量缩放关系
DOI：
10.1088/0004-637x/754/2/119
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Marrone D
中科院分区：
文献类型：
--
作者：
Marrone D
我们提出了第一个基于弱透镜的星系团质量，M WL，和综合康普顿参数Y SPH之间的标度关系。斯巴鲁8.2米望远镜和Sunyaev-Zel'dovich阵列获得了z = 0.2的18个星系团的观测结果。在Δ= 500、1000和2500 ρ c下测得的M WL-Y sph标度关系在斜率和归一化方面与先前在流体静力平衡（HSE）假设下得出的结果一致。我们发现在固定Y sph为20%时，M WL中的固有散射大于M HSE-Y sph散射的先前测量以及在模拟中发现的固定Y sph时的真实质量中的散射。此外，在我们的基于透镜的缩放关系中的散射是形态依赖的，与在r 500处相同Y sph处的干扰集群相比，未受干扰的M WL大30%-40%。进一步的研究表明，这种分离可能是由于我们的球形透镜模型不能忠实地描述星系团的三维结构，特别是沿着视线的结构。我们发现，最亮的星系团的椭圆率，代理晕的方向，以及相关的偏移量的质量从平均比例关系，这支持了这张照片。这提供了经验证据表明，视线投影效应是一个重要的系统的不确定性，在基于透镜的缩放关系。
We present the first weak-lensing-based scaling relation between galaxy cluster mass, M WL, and integrated Compton parameter Y sph. 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 M WL–Y sph scaling relations, measured at Δ= 500, 1000, and 2500 ρ c, are consistent in slope and normalization with previous results derived under the assumption of hydrostatic equilibrium (HSE). We find an intrinsic scatter in M WL at fixed Y sph of 20%, larger than both previous measurements of M HSE–Y sph scatter as well as the scatter in true mass at fixed Y sph found in simulations. Moreover, the scatter in our lensing-based scaling relations is morphology dependent, with 30%–40% larger M WL for undisturbed compared to disturbed clusters at the same Y sph at r 500. 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.