论文标题
Topz：J-PAS的光度红移
TOPz: Photometric redshifts for J-PAS
论文作者
论文摘要
随着专业强大的观察设施的发展，光度星系红移估计的重要性正在迅速增加。我们开发了一个新的光度红移估计工作流程TOPZ，为即将进行的大规模调查J-PA提供可靠，有效的红移估计，该估计将通过54个窄带过滤器观察到8500 deg2的8500 deg2。 Topz依靠基于模板的照片-Z估计以及一些添加的J-PAS特定功能和可能性。我们在Minijpas调查中介绍了Topz的性能，Minijpas调查是J-PAS调查的前体，并具有相同的滤波器系统。首先，我们使用合成的Galaxy Spectrum生成软件CIG来基于Minijpas源生成光谱模板。然后，我们通过最大程度地减少每个过滤器中模板通量的系统偏移来将校正校正到输入光度法。为了评估红移估计的准确性，我们使用了来自Deep2，Deep3和SDSS调查的光谱红移，该调查可用于1989年的Minijpas星系，r <22 magab。我们还测试了输入模板，Photo-Z先验和光度校正的选择和数量如何影响Topz红移精度。 Minijpas数据和Topz工作流程的总体表现达到了J-PAS红移准确性的期望。与以前的估计相似，我们发现38.6％的R <22 mag的星系达到DZ/（1 + Z）<0.003的J-PAS红移精度目标。限制模板集中的光谱数量可提高红移准确性高达5％，尤其是对于噪音为主导的噪声源。一旦实际的J-PAS数据可用，将进行进一步的改进。
The importance of photometric galaxy redshift estimation is rapidly increasing with the development of specialised powerful observational facilities. We develop a new photometric redshift estimation workflow TOPz to provide reliable and efficient redshift estimations for the upcoming large-scale survey J-PAS which will observe 8500 deg2 of the northern sky through 54 narrow-band filters. TOPz relies on template-based photo-z estimation with some added J-PAS specific features and possibilities. We present TOPz performance on data from the miniJPAS survey, a precursor to the J-PAS survey with an identical filter system. First, we generated spectral templates based on the miniJPAS sources using the synthetic galaxy spectrum generation software CIGALE. Then we applied corrections to the input photometry by minimising systematic offsets from the template flux in each filter. To assess the accuracy of the redshift estimation, we used spectroscopic redshifts from the DEEP2, DEEP3, and SDSS surveys, available for 1989 miniJPAS galaxies with r < 22 magAB. We also tested how the choice and number of input templates, photo-z priors, and photometric corrections affect the TOPz redshift accuracy. The general performance of the combination of miniJPAS data and the TOPz workflow fulfills the expectations for J-PAS redshift accuracy. Similarly to previous estimates, we find that 38.6% of galaxies with r < 22 mag reach the J-PAS redshift accuracy goal of dz/(1 + z) < 0.003. Limiting the number of spectra in the template set improves the redshift accuracy up to 5%, especially for fainter, noise-dominated sources. Further improvements will be possible once the actual J-PAS data become available.
