Purpose of the flight and payload description

The experiment has been performed in order to study the production of mesons in the interactions of cosmic-ray particles with hydrogen nuclei. The proton target consisted of a spherical metal Dewar, 30 cm in diameter, filled with hydrogen. Four crossed counter trays determined the direction of the incoming particle while two other counter trays detected multiple events. A master pulse was triggered by the coincidence. The pulses from each counter were in coincidence with the master pulse and were registered individually on a moving photographic film (hodoscope). Towards the middle of the flight the hydrogen was ejected from the Dewar. The remaining time at altitude was used as a control experiment without hydrogen.

Details of the balloon flight

Balloon launched on: 9/6/1950
Launch site: Stagg Field, University of Chicago, Illinois, US  
Balloon launched by: Chicago University Group
Balloon manufacturer/size/composition: Zero Pressure Balloon  
End of flight (L for landing time, W for last contact, otherwise termination time): 9/6/1950
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): F 4 h 30 m

External references

Images of the mission


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