Real-time measurement of low-energy-range neutron spectra on board the space shuttle STS-89 (S/MM-8).
We have developed a real-time, Bonner Ball-type (neutron energy range is from thermal to 15 MeV) neutron spectral measurement system (Bonner Ball Neutron Detector (BBND)) for use on board the International Space Station (ISS). From measurements taken inside STS-89 (S/MM-8), we successfully distinguished neutrons from protons and other particles in a mixed radiation field; a task hitherto considered difficult. Although the experimental period was short, only 3.5 days (January 24-27, 1998), we were able to obtain energy spectral data and the Earth's neutron dose-equivalent map for the ISS orbital conditions (altitude 400 km, orbit inclination angle 51.6 degrees). A method for calculating the neutron energy spectrum and compensating for the particle interaction with the sensors is also described in detail.
Matsumoto
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H
National Space Development Agency of Japan, Tsukuba Space Center, Office of Research and Development 2-1-1 Sengen, Tsukuba-shi, Ibaraki 305-8505, Japan. matsumoto.haruhisa@nasda.go.jp
Goka
T
T
Koga
K
K
Iwai
S
S
Uehara
T
T
Sato
O
O
Takagi
S
S
D000535:Aluminum; D001267:Atlantic Ocean; D019471:Elementary Particle Interactions; D004601:Elementary Particles; D005069:Evaluation Studies as Topic; D005214:Fast Neutrons; D005682:Gadolinium; D009010:Monte Carlo Method; D009502:Neutrons; D020959:Polyethylene; D011522:Protons; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000295:instrumentation*; D019445:Solar Activity; D013020:South America; D013026:Space Flight / Q000295:instrumentation*; D018531:Spacecraft / Q000295:instrumentation*
D011522:Protons; D020959:Polyethylene; D005682:Gadolinium; D000535:Aluminum