Measurements of cosmic-ray neutron energy spectra from thermal to 15 MeV with Bonner Ball Neutron Detector in aircraft

Yajima, Kazuaki*; Yasuda, Hiroshi*; Takada, Masashi*; Sato, Tatsuhiko; Goka, Tateo*; Matsumoto, Haruhisa*; Nakamura, Takashi*

Journal of Nuclear Science and Technology, 47(1), p.31 - 39, 2010/01

https://doi.org/10.3327/jnst.47.31

Cosmic-ray neutron energy spectra from thermal to 15 MeV were measured with the multi-moderator spectrometer named the Bonner Ball Neutron Detector (BBND) at aviation altitude (9-11 km). Four flights were carried out around the Nagoya Airport in Japan. The measured data were unfolded using the maximum entropy deconvolution code MAXED, and the derived spectra agreed with calculated results using PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) based on the Monte Carlo calculations by Particle and Heavy Ion Transport code System (PHITS). The results of the aircraft measurement verified the accuracy of model calculation.