Probing cosmology with weak lensing selected clusters – I. Halo approach and all-sky simulations
Probing cosmology with weak lensing selected clusters – I. Halo approach and all-sky simulations
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DOI：
10.1093/mnras/stv1854
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发表时间：
2015-04
影响因子：
4.8
通讯作者：
M. Shirasaki;T. Hamana;N. Yoshida
中科院分区：
文献类型：
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作者：
M. Shirasaki;T. Hamana;N. Yoshida
我们利用分析模型和大型数值模拟来探索通过宇宙剪切测量选择的星团的各种统计数据。我们首先开发一个光环模型来预测弱透镜效应选定簇的丰度和聚类情况。我们的模型中包含了星系形状噪声等观测效应。然后，我们生成真实的模拟弱透镜目录来测试我们的分析模型的准确性。为此，我们执行全天空光线追踪模拟，使我们能够对大的连续区域进行多种实现。我们使用明亮恒星的实际位置对天空上的遮蔽区域进行建模，并生成 200 个模拟弱透镜目录，天空覆盖范围为 1000 平方度。我们表明，我们的理论模型与统计数据的整体平均值及其直接从模拟目录计算出的协方差非常吻合。使用典型的选择阈值，忽略形状噪声校正会导致高估弱透镜选定簇的聚类，其水平约为 10%，并且形状噪声校正将簇丰度提高了几倍。我们使用光环模型计算互协方差，并考虑到由于掩模而导致的调查区域的有效减少。宇宙剪切自功率谱的协方差受到源自天空掩蔽的模式耦合效应的影响。我们的模型和结果可以很容易地用于正在进行和未来的弱透镜调查的宇宙学分析。
We explore a variety of statistics of clusters selected with cosmic shear measurement by utilizing both analytic models and large numerical simulations. We rst develop a halo model to predict the abundance and the clustering of weak lensing selected clusters. Observational eects such as galaxy shape noise are included in our model. We then generate realistic mock weak lensing catalogs to test the accuracy of our analytic model. To this end, we perform full-sky ray-tracing simulations that allow us to have multiple realizations of a large continuous area. We model the masked regions on the sky using the actual positions of bright stars, and generate 200 mock weak lensing catalogs with sky coverage of 1000 squared degrees. We show that our theoretical model agrees well with the ensemble average of statistics and their covariances calculated directly from the mock catalogues. With a typical selection threshold, ignoring shape noise correction causes overestimation of the clustering of weak lensing selected clusters with a level of about 10%, and shape noise correction boosts the cluster abundance by a factor of a few. We calculate the cross-covariances using the halo model with accounting for the eective reduction of the survey area due to masks. The covariance of the cosmic shear auto power spectrum is aected by the mode-coupling eect that originates from sky masking. Our model and the results can be readily used for cosmological analysis with ongoing and future weak lensing surveys.