Page "Explorer 35" Paragraph 4

This experiment consisted of a 12-cm Neher-type ionization chamber and two Lionel type 205 HT Geiger-Müller ( GM ) tubes.

The ion chamber responded omnidirectionally to electrons above 0. 7 MeV and protons above 12 MeV.

Both GM tubes were mounted parallel to the spacecraft spin axis.

GM tube 1 detected electrons above 45 keV that were scattered off a gold foil.

The acceptance cone for these electrons had a 70-deg full-angle and an axis of symmetry that was 20 deg off the spacecraft spin axis.

GM tube 2 responded to electrons and protons above 22 and 300 keV, respectively, in an acceptance cone of 70-deg full-angle centered at the spacecraft spin axis.

Both GM tubes responded omnidirectionally to electrons and protons of energies above 2. 5 and 50 MeV, respectively.

Pulses from the ion chamber and counts from each GM tube were accumulated for 39. 72 s and read out every 40. 96 s. In addition, the time between the first ion chamber pulses in an accumulation period was also telemetered.

This experiment performed well initially.