论文标题
对宇宙学参数估计的传播空间变化剪切偏差，用于IV期弱透明调查
Propagating spatially-varying multiplicative shear bias to cosmological parameter estimation for stage-IV weak-lensing surveys
论文作者
论文摘要
我们考虑由空间变化的乘法剪切偏置（M偏置）引入的偏置在层析成像宇宙剪切角功率光谱上。为了计算功率光谱中的偏差，我们使用计算效率的伪CL方法估算了与M偏置图关联的模式耦合矩阵。这使我们可以考虑M偏置对高L的影响。然后，我们进行Fisher基质分析以预测宇宙学参数的偏见。对于具有空间变化的M偏置（零平均值且RMS为0.01）的类似欧几里克的调查，我们发现参数偏差最大值的预期统计误差的最大约为10％，如果包括多数乘以L_MAX = 5000。我们得出的结论是，在即将进行的弱透镜调查中，对空间变化的M偏置的影响可能是对误差预算的次要主流但潜在的不可忽略的贡献。我们还研究了参数偏差对M偏差场空间变化的幅度和角度尺度的依赖性，并得出结论，除了对平均值的任何要求外，还应对M偏置空间变化的RMS进行要求。我们发现，对于像欧几里得一样的调查，偏差通常超过M -bial RMS 0.02-0.03的统计误差的〜30％，并且可能超过RMS的统计误差〜0.04-0.05。这允许将要求设置为M偏差的空间变化的允许幅度，而M偏置将由于即将进行的弱透镜测量结果而产生的系统。
We consider the bias introduced by a spatially-varying multiplicative shear bias (m-bias) on tomographic cosmic shear angular power spectra. To compute the bias in the power spectra, we estimate the mode-coupling matrix associated with an m-bias map using a computationally-efficient pseudo-Cl method. This allows us to consider the effect of the m-bias to high l. We then conduct a Fisher matrix analysis to forecast resulting biases in cosmological parameters. For a Euclid-like survey with a spatially-varying m-bias, with zero mean and rms of 0.01, we find that parameter biases reach a maximum of ~10% of the expected statistical error, if multipoles up to l_max = 5000 are included. We conclude that the effect of the spatially-varying m-bias may be a sub-dominant but potentially non-negligible contribution to the error budget in forthcoming weak lensing surveys. We also investigate the dependence of parameter biases on the amplitude and angular scale of spatial variations of the m-bias field, and conclude that requirements should be placed on the rms of spatial variations of the m-bias, in addition to any requirement on the mean value. We find that, for a Euclid-like survey, biases generally exceed ~30% of the statistical error for m-bias rms 0.02 - 0.03 and can exceed the statistical error for rms ~0.04 - 0.05. This allows requirements to be set on the permissible amplitude of spatial variations of the m-bias that will arise due to systematics in forthcoming weak lensing measurements.
