Photoelectric observations in a wide-field area around the Praesepe cluster

The PPM catalogue numbers, photoelectric magnitudes V, color-indexes U – B, B – V, V – R and rms errors of their determinations for 51 stars of the secondary wide-angle photoelectric standard are published. The catalogue accuracy of quantities mentioned above is 0.007, 0.015, 0.006, 0.006 mag, respectively. A list of ten stars which are probably variable is published.     

UBV光电测光系统的转换方程和精度比较

根据对鬼星团中Ｊｏｈｎｓｏｎ测光标准星的观测，我们研究了北京天文台６０ｃｍ望远镜直流光电光度计ＵＢＶ测光系统的转换方程．应用该方程推算了对三颗变星观测得到的ＵＢＶ星等，讨论了所得光变曲线的精度，并与较差方法所得结果进行了比较     

DCMT光电测微器的数据采集系统

光电测微器是中－丹水平子午环最关键的部分．本文介绍了数据采集系统的设计思想．根据长期对仪器的测试和观测结果分析，表明系统完全达到设计要求，同时为下一步改装成ＣＣＤ终端，观测极限星等达１７ｍ．５提供了可行的方案．     

中国等高仪星表的现状和未来

自七十年代后期起，中国的４架光电等高仪就开始注重于旨在改进基本星表系统的观测．这４架光电等高仪均实现了现代化改造：实现全自动化操作和采用光子计数记录，这使得仪器能通宵达旦地工作，效率倍增．近年来用中国光电等高仪的观测已经编算出几部等高仪星表，其两个坐标（α和δ）的精度都很好，极限三等可达１１ｍ以上．将来这４架光电等高仪和即将用ＣＣＤ装备的Ⅲ型光电等高仪将会对基本天体测量做出更大贡献．     

日晕光度计的研制和初步观测结果

本文从日冕观测和研究的意义出发，叙述了用外遮档及小孔减光测量日晕光度的方法以及在云南和新疆若干选点的初步观测结果。     

Saao standards for optical photometry

A review is given of the development of systems of photometric standard stars at the South African Astronomical Observatory. A brief historical perspective indicates how the Harvard E-regions were chosen as standard sequences and developed into a very precise Southern hemisphere system for UBV(RI) _c photometry. Subsequent additions of Strömgrenuvby - H and DDO photometry to samples of E-region stars and UBV(RI) _c extensions to the F-regions and the Magellanic Clouds are also described. Current programmes to extend and improve these standard stars are briefly discussed, as well as the long-standing problem of linking the Northern and Southern systems.     

光子计数式光电测光系统数据采集和控制软件

本文报告了数据采集和控制软件ＣＭＵＯＰＰＳ的研制情况，这个软件是云南天文台密近双星研究组为泰国清迈大学天文台研制的光子计数式光电测光系统的专用配套软件。文中给出了硬件接口的性能及软件和硬件握手的方案，介绍了软件的总体概况，还说明了软件的使用环境和使用方法。最后给出了实验室测试和试观测过程中软件的运行情况及结果。     

A photometric study of the Algol-type binary AB Cas

We present new photoelectric observations of the eclipsing binary system AB Cas, together with an analysis of the light curves. Using the available times of light minimum reported in the literature together with our own minima, period changes are monitored, and the possible third-body parameters are obtained. The absolute properties of the system and the delta-Scuti behavior of the primary are also discussed.