The UCSD OSO-7 X-ray telescope was designed to detect X-rays in the range from about 7 to 550 keV. It consisted of a 1 cm thick NaI(Tl) crystal inside a massive CsI(Na) anticoincidence shield. There were 128 energy loss channels. Each event signature also contained a clock time good to 0.625 ms. The field of view was 6.5 degrees FWHM and the sensitive area was ~ 64 sq-cm. The total detector weight was 85 lbs.
The UNH gamma-ray monitor consisted of a 7.6 cm x 7.6 cm NaI(Tl) scintillator which operated in the range 300 keV - 10 MeV. The detector was surrounded on all sides by a ~ 4 cm thick CsI(Na) scintillator cup. The exception was a forward aperture which was covered by a 0.5 cm thick CsI(Na) slab. The instrument was calibrated regularly each orbit with a 60Co source. The resolution was 7.8% at 662 keV. The instrument was in the wheel section of OSO-7. Data were accumulated in 0.5 s bins when the detector was looking at the Sun/anti-Sun during each 2-s spin. The monitor operated until 25 December 1972, but was usually turned off during the periodic penetration of the satellite into the radiation belts.
The UCSD experiment produced results on Cyg X-3 which showed the 4.8-hr period present in the 6-21 keV range, but not in the 21-98 keV range.
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