DQ Herculis: Synchronous Photometry.
Synchronous signal averaging, applied to the photometry of the steller system DQ Herculis in order to study the 71.1-second pulsations discovered by Walker in 1956, yields a light curve which is a pure sinusoid, within the accuracy of measurement. The binary period is increasing, probably as a result of mass lost from the system.
Nather
R E
RE
Warner
B
B