MAGNETIC SPECTROMETER

The apparatus, uses magnetic-core digital spark chambers to determine the trajectories of charged particles through the instrument, before and after they pass the gap of a permanent magnet. The direction and magnitude of the magnetic deflection provides the sign and rigidity of each particle traversing the detector. The spark chambers are triggered by a counter telescope consisting of a directional gas Cerenkov counter and two plastic scintillation counters. In addition, two anti-coincidence scintillation counters are used to veto events in which a particle fails to pass through the magnet gap.

Balloon launched on: 8/3/1974 at 20:30 cst
Launch site: Fort Churchill Airport, Manitoba, Canada  
Balloon launched by: Raven Industries Inc.
Balloon manufacturer/size/composition: Zero Pressure Balloon Winzen 50.300.000 cuft (Natural Shape - 0.5 mil. Stratofilm + 2 0.7 mil. Caps)
End of flight (L for landing time, W for last contact, otherwise termination time): 8/4/1974 at ~ 12:00 cst
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 16 h 20 m
Landing site: In the Athabasca River area, Alberta Canada
Campaign: SKYHOOK CHURCHILL 74  
Payload weight: 800 lbs

• Cosmic ray positron and negatron spectra between 20 and 800 MeV measured in 1974 NASA report N75-28000, June 1975
• Cosmic-ray positron and negatron spectra between 20 and 800 MeV measured in 1974 Astrophysical Journal, vol. 204, Mar. 15, 1976, pt. 1, p. 927-933
• Largest balloon launched by ONR Naval Research Reviews, November 1974, Page 13
• Stratofilm balloon flight record - in Flight Report Issue 1, 1975 - Winzen Research Inc. (StratoCat's private collection)
• Progress in Scientific Balloon Technology in European Programmes on Sounding-Rocket and Balloon Research in the Auroral Zone, May 1976, p. 283