Electronics in astronomy: Early applications of the photoelectric cell and photomultiplier for studies of point-source celestial phenomena

Photoelectric detection devices have been in use in astronomy for over 80 years, but gained wide popularity and utility only since World War II. After the turn of the Century, early photoconductive selenium cells were quickly replaced by photoemissive cells utilizing potassium hydride photocathodes, and then by photoelectric photomultipliers amplified by vacuum tube dc circuits. As the reliability and sensitivity of photoelectric systems increased, and as electronic components became more accessible, more and more astronomers turned to this new technology to measure with previously unobtainable precision the brightness of celestial objects. This paper identifies those who helped to improve and apply electronic detector technology to astronomy. Their research interests and backgrounds will be discussed, as will the role of World War II in bringing astronomers into contact with electronic technology.