Purpose of the flight and payload description
LEE was an instrument which measured the energy spectrum of comic ray electrons. In the picture at left we can see a scheme of it. It detects incoming electrons with 3 plastic scintillators (T1, T3 and G in the drawing) the last one for anticoincidence and a gas Cherenkov detector (T2). The electron energy is measured in a cesium iodide (T4) and leadglass (T5) calorimeter. Another Scintillator (T6) also assists in particle identification and energy determination by counting the number of particles that escape the calorimeter.
The LEE instrument was developed in the late 60's at the University of Chicago and made his first flight in 1968. Over time, regular ballon flights have been made from Northern Canada every year from 1968 to 1975 and approximately bi-annually until 1979. Then, the experiment was transfered to the University of Delaware, wich now operates it.
The observations obtained by LEE provided very precise measurements of the electron spectrum over an extended period of time.
Details of the balloon flight
Balloon launched on: 7/11/1971
Launch site: Fort Churchill Airport, Manitoba, Canada
Balloon launched by: Raven Industries Inc.
Balloon manufacturer/size/composition: Zero Pressure Balloon Winzen Stratofilm 15.000.000 cuft - Natural Shape (0.5 mils) - 2 Caps (0.5 Mils.)
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 10h 12m
Payload weight: 973 lbs