Accurate weak lensing mass estimates of clusters are needed in order to calibrate mass proxies for the cosmological exploitation of galaxy cluster surveys. Such measurements require accurate knowledge of the redshift distribution of the weak lensing source galaxies. In this context, we investigate the accuracy of photometric redshifts (photo-$z$s) computed by the 3D-HST team for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey fields, which provide a relevant photometric reference data set for deep weak lensing studies. Through the comparison to spectroscopic redshifts and photo-$z$s based on very deep data from the Hubble Ultra Deep Field, we identify catastrophic redshift outliers in the 3D-HST/CANDELS catalogue. These would significantly bias weak lensing results if not accounted for. We investigate the cause of these outliers and demonstrate that the interpolation of spectral energy distribution (SED) templates and a well-selected combination of photometric data can reduce the net impact for weak lensing studies.

中文翻译：

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测试 3D-HST 光度红移估计作为深弱透镜研究参考样本的准确性

需要对星团进行准确的弱透镜质量估计，以便为星系团调查的宇宙学开发校准质量代理。这种测量需要准确了解弱透镜源星系的红移分布。在此背景下，我们研究了 3D-HST 团队为宇宙组装近红外深河外遗产勘测场计算的光度红移 (photo-$z$s) 的准确性，这为深层弱光提供了相关的光度参考数据集。透镜研究。通过与基于哈勃超深场的非常深的数据的光谱红移和 photo-$z$s 的比较，我们在 3D-HST/CANDELS 目录中确定了灾难性的红移异常值。如果不加以考虑，这些将显着偏向弱透镜结果。