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The Galileo Energetic Particles Detector


Galileo EPD Handbook


Chapter 1. Instrument Summary


EPD Flight Particle Calibration Sources


Source: R. McEntire, SDO/PAO-0040, January 20-21,1981


 A suggested list of sources that would be placed on the foreground shield for flight calibration is contained in Table 21. Barium 133 would give 70 percent 45 keV electrons, and 10 percent 75 keV, 266 keV, and 319 keV electrons, respectively. To give 10 counts per second after injection at Jupiter, an initial source strength of 2 mc would be required (half life is about 7 1/2 years).  Americium 241 could be used to calibrate the A detector by using a foil to lower the energy of the alpha particles in units to 200 keV.


In the CMS in front of Ja', a cocktail source of Americium and Gadolinium will give two distinct energy peaks in the DE by E matrix.  An Americium source degraded by a foil to H1.3 MeV will be placed in front of the Jc' detector.


Table 21. EPD Flight Calibration Sources (nominal)


Ba-133 (2 microcurie) 45, 75, 266, 319 keV electrons
~10 cps total at injection
Am-241 (3.4 microcurie) 5.48 MeV alpha line degraded by foil to 200 keV (FWHM ~ 200 keV)
~10 cps
Ja' Am-241 (0.05 microcurie) + Gd-148 (0.05 microcurie)
5.48 + 3.18 MeV alphas
~2 cps/peak
Jc' Am-241 (0.1 microcurie) degraded by foil to ~1.3 MeV alphas
~4 cps



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Updated 8/23/19, Cameron Crane


Manufacturer: The Galileo Spacecraft was manufactured by the Jet Propulsion Laboratory, Messerschmitt-Bölkow-Blohm, General Electric, and the Hughes Aircraft Company.

Mission Duration: Galileo was planned to have a mission duration of around 8 years, but was kept in operation for 13 years, 11 months, and 3 days, until it was destroyed in a controlled impact with Jupiter on September 21, 2003.

Destination: Galileo's destination was Jupiter and its moons, which it orbitted for 7 years, 9 months, and 13 days.