利用星系双点关联函数确定光谱红移分布的星系

我们研究了如何从星系角双点关联函数中确定按光谱红移二分箱排序的星系红移分布。我们发现，重构的红移分布不确定性在每个红移二分箱中使用的参数数量以及角尺度范围方面至关重要，但与光谱红移二分箱的数量无关。在每个光谱红移二分箱中使用六个参数，并限制 ourselves to angular scales over which the galaxy number counts are normally distributed, we find that errors in the reconstructed redshift distributions are large; i.e., they would be the dominant source of uncertainty in cosmological parameters estimated from otherwise ideal weak lensing or baryon acoustic oscillation data. However, either by reducing the number of free parameters in each redshift bin, or by (unjustifiably) applying our Gaussian analysis into the non-Gaussian regime, we find that the correlation functions can be used to reconstruct the redshift distributions with moderate precision; e.g., with mean redshifts determined to around 0.01. We also find that dividing the galaxies into two spectral types, and thereby doubling the number of redshift distribution parameters, can result in a reduction in the errors in the combined redshift distributions.