Purpose of the flight and payload description

The goal of the flight was to measure atmospheric X-rays, namely secondary X-radiation from cosmic rays, for the energy interval 30-155 keV and to compare the data of the flux measured at the Pfotzer maximum with those obtained previously by several research groups at other latitudes and with a similar technique.

The detector consisted of a Harshaw NaI(T1) crystal with dimensions 3 x 1/2 inches, set up to look upward. The effective area was 30.4 cm2 and the efficiency was assumed equal to one for the energy range of interest, namely 30 - 155 keV. A 64-channel pulse height analyzer (PHA) was provided covering this energy range. A differential discriminator for the whole energy range with a scaling factor of 16 was also available. The data from the PHA were telemetered serially on a pulse-code-modulation channel. The flight used a FM-FM telemetry system and the data were telemetered to ground along with assorted payload housekeeping information. The flight's duration was defined by the telemetry range, as well as by the prospect of an easy recovery.

Details of the balloon flight

Balloon launched on: 12/18/1981 at 3:00 local
Launch site: National Institute of Space Research, Sao Jose dos Campos, Sao Paulo, Brazil  
Balloon launched by: Instituto Nacional de Pesquisas Espaciais (INPE)
Balloon manufacturer/size/composition: Zero Pressure Balloon  
End of flight (L for landing time, W for last contact, otherwise termination time): 12/18/1981 at 8:43 local
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 5 h 43 m

External references

If you consider this website interesting or useful, you can help me to keep it up and running with a small donation to cover the operational costs. Just the equivalent of the price of a cup of coffee helps a lot.