The MICE Grand Challenge light-cone simulation – III. Galaxy lensing mocks from all-sky lensing maps
The MICE Grand Challenge light-cone simulation – III. Galaxy lensing mocks from all-sky lensing maps
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DOI：
10.1093/mnras/stu2464
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发表时间：
2013-12
影响因子：
4.8
通讯作者：
P. Fosalba;E. Gaztañaga;F. Castander;M. Crocce
中科院分区：
文献类型：
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作者：
P. Fosalba;E. Gaztañaga;F. Castander;M. Crocce
在本系列的第1篇论文（Fosalba et al. 2013）中，我们提出了一个新的n体光锥模拟，来自MICE合作，MICE大挑战（MICE- gc），在（3gpc）^3的移动体积中包含约700亿个暗物质粒子，我们使用光晕占位分布和光晕丰度匹配技术建立了光晕和星系目录，如配套论文II （Crocce et al. 2013）中所述。鉴于其巨大的体积和精细的质量分辨率，MICE-GC模拟还可以对即将到来的广域和深星系调查中的透镜观测结果进行精确建模。在本系列的最后一篇论文（论文III）中，我们描述了按照“洋葱宇宙”方法（Fosalba et al. 2008）构建的全天透镜图，并讨论了它们在亚弧分空间分辨率下z=1.4光锥中的特性。通过比较MICE-GC与低质量分辨率（即粒子质量~ 10^11 Msun）模拟的收敛功率谱，我们发现多极l ~ 10^3的分辨率效应为5%，l ~ 10^4的分辨率效应为20%。通过将MICE-GC与Takahashi等人2012年最近的数值拟合进行比较，可以看出，分辨率效应对我们的模拟的影响要小得多。我们使用全天透镜映射来模拟星系的透镜特性，如收敛、剪切、透镜星等和位置，并使用星系剪切自相关和谐波空间和组态空间中的相互关联来彻底验证它们。我们的结果表明，这里提出的星系透镜模型可以用来精确地模拟透镜观测到的弧分尺度。
In paper I of this series (Fosalba et al. 2013), we presented a new N-body lightcone simulation from the MICE collaboration, the MICE Grand Challenge (MICE-GC), containing about 70 billion dark-matter particles in a (3 Gpc)^3 comoving volume, from which we built halo and galaxy catalogues using a Halo Occupation Distribution and Halo Abundance Matching technique, as presented in the companion Paper II (Crocce et al. 2013). Given its large volume and fine mass resolution, the MICE-GC simulation also allows an accurate modeling of the lensing observables from upcoming wide and deep galaxy surveys. In the last paper of this series (Paper III), we describe the construction of all-sky lensing maps, following the "Onion Universe" approach (Fosalba et al. 2008), and discuss their properties in the lightcone up to z=1.4 with sub-arcmin spatial resolution. By comparing the convergence power spectrum in the MICE-GC to lower mass-resolution (i.e., particle mass ~ 10^11 Msun) simulations, we find that resolution effects are at the 5 % level for multipoles l ~ 10^3 and 20 % for l ~ 10^4. Resolution effects have a much lower impact on our simulation, as shown by comparing the MICE-GC to recent numerical fits by Takahashi et al 2012. We use the all-sky lensing maps to model galaxy lensing properties, such as the convergence, shear, and lensed magnitudes and positions, and validate them thoroughly using galaxy shear auto and cross-correlations in harmonic and configuration space. Our results show that the galaxy lensing mocks here presented can be used to accurately model lensing observables down to arcminute scales.