UBVRI Photometric Standard Stars

本研究计画的目标是增强、发展并发表微弱的标准星星序列。长期以来，人们一直需要在各种光学波长下具有已知强度和颜色的精确光度标准星。使用这些标准恒星可以将不同研究者对不同天体现象的亮度和颜色测量结果进行组合和相互比较。用途的例子包括校准天体的星等和颜色指数，以进一步了解恒星的演化、星星团的年龄和距离、变星的研究，以及确定通过我们的银河系、本星系群和宇宙边缘的距离尺度。在这里，利用智利Cerro Tololo Interamerican天文台的望远镜，Landolt博士将完成新标准恒星的开发，这些恒星将比现有恒星暗100倍。他还将在亚利桑那州的基特峰国家天文台开始开发下一组更暗的标准恒星。这些校准星是目前建造的、正在建造的和处于规划阶段的最大的地基和天基光学探测器的整个集合所需要的，并且将可用于这些光学探测器。本项目的总体目标是将校准序列扩展到更微弱的极限，以便解释的极限是科学的，而不是校准的极限。

The goal of this research project is to enhance, develop, and publish faint standard star sequences. There is a long-term need for accurate photometric standard stars with known intensities and colors at a variety of optical wavelengths. Use of such standard stars permits the combination and inter-comparison of the brightness and color measurements of different celestial phenomena made by different investigators. Examples of uses include the calibration of magnitudes and color indices of celestial objects to further the understanding of stellar evolution, ages and distances of star clusters, studies of variable stars, and to define the distance scale through our Milky Way Galaxy, the local group of galaxies, and onward to the edge of the Universe. Here, using telescopes at the Cerro Tololo Interamerican Observatory in Chile, Dr. Landolt will complete the development of new standard stars that will be about 100 times fainter than those now available. He will also begin development of the next set of even fainter standard stars at the Kitt Peak National Observatory in Arizona. These calibration stars are needed for, and will be usable by the entire ensemble of the largest ground-based and space-based optical detectors, both presently built, those under construction, and those in the planning stage. The overall goal of this project is to extend the calibration sequences to fainter limits so the limits of interpretation will be scientific, and not those of calibration.