Astronomy by using the data of Sloan Digital Sky Survey

日美合作的斯隆数字天文测量(SDSS)项目从1999年开始进行调试观测，2001年完成了天赤道的测量。在这次试运行观测中，取得了许多重要的天文现象，如发现了z=6.28最大的类星体，发现了1万多个类星体。包括红移大于5的星系，测量超过10万个星系的红移，用一百万颗恒星研究我们星系的基本结构，以及低温恒星序列的确定。这些显著的成果已经在30多篇论文中发表。特别是，通过五色光度法等独特的观测，已经发现了十多个红移大于5的类星体，并由此可以清楚地了解早期宇宙中类星体的数量演化。对于星系，我们已经获得了一万个星系的均匀光度数据，目前正在探索光度函数、空间分布、数量演化和类型分类等统计研究。这些数据中的一部分已经公布，以供进一步研究，世界上的天文学家正在尝试使用大型望远镜对有趣的物体进行更详细的观测。只有SDSS才有可能进行五色光度测量，它将在下一次北半球调查中带来更多重要数据。SDSS的日本促进小组(JPG)为探测器的维护、数据获取和数据分析作出了贡献，他们作为合著者出现在所有文件中。

The Sloan Digital Sky Survey (SDSS) Project, which are proceeded by Japan-US collaboration, has began the commissioning observations from 1999 and finished the survey of celestial equator in 2001. In this commissioning observations, many important astronomical phenomina have been obtained such as the discovery of the farest quasar at z=6.28, the discovery of more than ten thousand quasars . including those with redshifts higher than 5, the measurement of redshifts of galaxies more than one hundred thousands, the study of fundamental structure of our galaxy by using one million stars and the confiramtion of the sequnceof low temperature stars. These remarkable results are already published by more than thirty papers. Especially, by unique observations as five-color photometry more than ten quasars with redshifts higher than 5 have beeb discovered, and from this result we can make clear the number evolution of quasars at early universe. As for galaxies, we got homogeneous photometric data of ten thousand galaxies and now such statistical studies as luminosity function, spatial distribution, number evolution and type classification are exploring. A part of these data are already released for further studies and astronomers in the world are attempting much detailed observations of interesting objects by using large telescopes. The five-color photometry is possible only by SDSS, and it will bring much more important data in the next survey of northern hemisphere. The Japan Promotion Group (JPG) of SDSS have contributed to the maintenance of detectors, the data acquision and the data analysis, and they aapeared in all papers as co-authors.10