Long-Term Observations of Cygnus X-2 from OSO-7

This paper reports the results of observations of Cyg X-2 made with the UCSD OS 0-7 X-ray telescope during the intervals 1972 January 9-16, 1972 January 21-26, and 1972 July 8-11. Random factor-of-two variations were found in the data. The average flux over the 7-18 keV range was 0.093 I 0.003 photons 5 1and the 2a upper limit in the 18-47 keV range was 0.012 photons cm-2 -2 The energy spectrum could be fitted with an exponential I - with 3 < kT < 10 keV. Subject headings: spectra, X-ray - X-ray sources