Sloan Digital Sky Survey Standard Star Catalog for Stripe 82: The Dawn of Industrial 1% Optical Photometry
Sloan Digital Sky Survey Standard Star Catalog for Stripe 82: The Dawn of Industrial 1% Optical Photometry
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DOI：
10.1086/519976
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发表时间：
2007-03
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影响因子：
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通讯作者：
Ž. Ivezić;J. A. Smith;G. Miknaitis;Huan Lin;D. Tucker;R. Lupton;J. Gunn;G. Knapp;M. Strauss-M.-Str
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文献类型：
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作者：
Ž. Ivezić;J. A. Smith;G. Miknaitis;Huan Lin;D. Tucker;R. Lupton;J. Gunn;G. Knapp;M. Strauss-M.-Str
我们描述了在 ugriz 系统中使用多个 SDSS 光度观测（每个波段至少 4 个，中位数为 10）构建的标准星表。该目录包括来自赤道带 82 (|δJ2000.0| < 1.266°) 的 101 万个不变的未解析天体，位于赤经范围 20h34m-4h00m 内，相应的 r 波段（近似约翰逊 V 波段）星等在 14-22 范围内。各个源的测量分布表明，光度管道正确估计了随机光度误差，对于 ugriz 中亮度分别高于 19.5、20.5、20.5、20 和 18.5 的恒星，随机光度误差低于 0.01 星等（大约是单独 SDSS 运行的两倍）。内部一致性的多项独立测试表明，光度零点的空间变化不大于∼0.01 mag (rms)。该目录除了是最大的可用光学光度测量数据集，内部一致性达到~1% 水平外，还提供了 SDSS 光度测量系统的实用定义。使用该目录，我们表明，即使对于通过 1 星等厚云获得的数据，SDSS 观测运行的光度零点也可以在 2% 的标称不确定度内进行校准，并且我们仅使用光度数据证明了 He 和 H 白矮星序列的存在。根据该目录的属性，我们得出结论，即将到来的大规模光学巡天（例如大型综合巡天望远镜）将能够为数十亿个光源提供可靠的 1% 光度测量。
We describe a standard star catalog constructed using multiple SDSS photometric observations (at least four per band, with a median of 10) in the ugriz system. The catalog includes 1.01 million nonvariable unresolved objects from the equatorial stripe 82 (|δJ2000.0| < 1.266°) in the right ascension range 20h34m-4h00m and with the corresponding r-band (approximately Johnson V-band) magnitudes in the range 14-22. The distributions of measurements for individual sources demonstrate that the photometric pipeline correctly estimates random photometric errors, which are below 0.01 mag for stars brighter than 19.5, 20.5, 20.5, 20, and 18.5 in ugriz, respectively (about twice as good as for individual SDSS runs). Several independent tests of the internal consistency suggest that the spatial variation of photometric zero points is not larger than ∼0.01 mag (rms). In addition to being the largest available data set with optical photometry internally consistent at the ∼1% level, this catalog provides a practical definition of the SDSS photometric system. Using this catalog, we show that photometric zero points for SDSS observing runs can be calibrated within a nominal uncertainty of 2% even for data obtained through 1 mag thick clouds, and we demonstrate the existence of He and H white dwarf sequences using photometric data alone. Based on the properties of this catalog, we conclude that upcoming large-scale optical surveys such as the Large Synoptic Survey Telescope will be capable of delivering robust 1% photometry for billions of sources.