From the COMBO-17 catalog in the CDFS (Chandra Deep Field South), 1231 faint blue galaxies with photometric redshift 0.1 ＜ z ＜ 0.3 are selected. The photometric redshifts of this sample have been studied by only using the optical data and by using the optical and infrared data, respectively. The result shows that there are 183 galaxies with redshifts greater than 1.2 when using optical and infrared data to infer the photometric redshifts. This study also shows that increasing the photometric signal-to-noise ratio can also help to improve the precision of the photometric redshift. The rest-frame SEDs (Spectral Energy Distributions) of these galaxies also have been investigated. The observational near-infrared fluxes tend to be larger than the optical fluxes for high-redshift galaxies, while the observational near-infrared fluxes tend to be less than the optical fluxes for low-redshift galaxies.%从COMBO-17数字巡天数据里,选择了CDFS(Chandra Deep Field South)天区中1 231个测光红移在0.1～0.3之间的暗蓝星系作为样本,研究了这些星系分别在只有光学波段和光学加近红外波段数据情况下做测光红移得到的红移分布,以及这些星系在静止参考系下的能谱分布(Spectral Energy Distributions,SEDs)特征.结果表明有183个星系在利用光学加近红外波段数据做测光红移时得到的红移大于1.2,它们的误差为0.046,提高测光的信噪比也有利于区分这类被光学波段误认为低红移的星系.这些暗蓝星系中高红移星系的观测近红外流量相对于光学流量有上升的趋势,而低红移星系的观测近红外流量相对于光学流量有下降的趋势.
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