HEXAGONE (High Energy X-ray And Gamma ray Observatory for Nuclear Emissions)

The instrument is a high resolution gamma-ray spectrometer and consists of an array of twelve cooled germanium detectors.

Balloon launched on: 5/22/1989 at 20:45 utc
Launch site: Australian Balloon Launching Station, Alice Springs, Australia  
Balloon launched by: National Scientific Balloon Facility (NSBF)
Balloon manufacturer/size/composition: Zero Pressure Balloon N29-8/8/8T.28.40
Balloon serial number: R28.40-2-118
Flight identification number: 270N
End of flight (L for landing time, W for last contact, otherwise termination time): 5/23/1989 at 16:56 utc
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 5 h
Landing site: 130 miles WSW of Mackay, Queensland, Australia

• Annihilation Radiation and Associated Continuum from the Galactic Center Region 23rd International Cosmic Ray Conference, Vol. 1, p.148
• Compton-backscattered annihilation radiation from the Galactic Center region Astrophysical Journal, Part 1, vol. 414, no. 1, p. 165-177
• HEXAGONE observation of the Galactic center gamma-ray continuum Astronomy and Astrophysics Supplement Series, vol. 97, no. 1, p. 199-203
• High energy astronomy program at UCSD Advances in Space Research Volume 14, Issue 2, Pag. 151
• High energy observation of the Galactic center region 511 keV and Al-26 lines with HEXAGONE Astronomy and Astrophysics Supplement Series, vol. 97, no. 1, p. 185-187
• Information about HEXAGONE Gamma-Ray Astronomy group of the University of California website
• NASA Balloon Flights (1989-1998) in NASA Historical Data Book, Vol. VII: NASA Launch Systems, Space Transportation, Human Spaceflight, and Space Science, 1989-1998
• Observation of SN 1987A with the gamma-ray spectrometer HEXAGONE Astrophysical Journal, Part 1, vol. 403, no. 1, p. 332-335.
• Observation of the 511 keV annihilation line in the direction of the galactic center with HEXAGONE AIP Conf. Proc. 232, 52 (1991)
• Observations of SN1987A and the Galactic Center with a New High Resolution Gamma-Ray Spectrometer 21st International Cosmic Ray Conference. Volume 2 (OG Sessions), p.174
• Positrons annihilation and the Galactic center Thesis by Wallyn, Pierre - Universite de Paris
• Traitement des donnees de l'experience HEXAGONE: Regions centrales de la Galaxie et SN1987 A. Interpretation Thesis by Chapuis, Claude - Universite de Paris