DGT (Directional Gamma-Ray Telescope)

A first-generation (balloon-borne) coded-aperture imaging telescope covering the energy range 160 keV - 10 MeV using an array of BGO scintillators as a detection plane.

It was capable of imaging photons in the 160 keV to 10 MeV energy range.

This was the first flight and due to the balloon fail, no scientific data was obtained.

Balloon launched on: 9/30/1982 at 00:36 utc
Launch site: Columbia Scientific Balloon Facility, Palestine, Texas, US  
Balloon launched by: National Scientific Balloon Facility (NSBF)
Balloon manufacturer/size/composition: Zero Pressure Balloon Winzen - 726.614 m3 (15.24 microns) SF408.33-060-NSCR-01
Balloon serial number: W25.66-2-01
Flight identification number: 1311P
End of flight (L for landing time, W for last contact, otherwise termination time): 9/30/1982 at 1:42 utc
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): ~1 h
Landing site: Balloon failure at 60.000 ft. Landing 20 miles SW of Frankston, Texas, US
Payload weight: 1059 kgs
Overall weight: 1600 kgs

The telescope was succesfull launched on September 30, 1982 but after an hour of ascent and before reach float altitude, the balloon failed.

The payload landed in a Texas cow pasture with the balloon wrapped around it (see picture at right).

• A Balloon-Borne Coded Aperture Telescope for Low-Energy Gamma- Ray Astronomy Nuclear Instruments and Methods in Physics Research A274 (1989) 362
• Gamma-ray imaging observations of the Crab and Cygnus regions Ph.D Thesis by Mark Lewis McConnell, University of New Hampshire, 1987
• National Scientific Balloon Facility Annual Report FY 1982 National Center for Atmospheric Research, February 1983
• Observations of cosmic gamma ray sources and their contribution to the diffuse gamma ray background Ph.D Thesis by Debadarshi Bhattacharya, University of New Hampshire, 1990