Altitude variation of cosmic-ray neutrons

Journal Article · Sun Nov 01 04:00:00 EST 1987 · Health Phys.; (United States)

DOI:https://doi.org/10.1097/00004032-198711000-00008· OSTI ID:5557530

Nakamura, T; Uwamino, Y; Ohkubo, T; Hara, A

The altitude variation of the cosmic-ray neutron energy spectrum and the dose equivalent rate was measured at an average geomagnetic latitude of 24 degrees N by using the high-efficiency multi-sphere neutron spectrometer and neutron dose-equivalent counter developed by the authors. The data were obtained from a 2-h flight over Japan on 27 February 1985. The neutron energy spectra measured at sea level and at altitudes of 4880 m and at 11,280 m were compared with the calculated spectra of O'Brien and with other experimental spectra, and they are in moderately good agreement with them. The dose equivalent rate increases according to a quadratic curve up to about 6000 m and then increases linearly between 6000 m and 11,280 m. The dependence of dose equivalent rates at sea level and at an altitude of 12,500 m on geomagnetic latitude also is given by referring to other experimental results.

• Research Organization: Tohoku Univ., Sendai, Japan
• OSTI ID: 5557530
• Journal Information: Health Phys.; (United States), Journal Name: Health Phys.; (United States) Vol. 53:5; ISSN HLTPA
• Country of Publication: United States
• Language: English

Related Subjects

560150* -- Radiation Effects on Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALTITUDE
BARYONS
COSMIC RADIATION
DOSE EQUIVALENTS
DOSES
ELEMENTARY PARTICLES
FERMIONS
HADRONS
IONIZING RADIATIONS
MEASURING INSTRUMENTS
MONITORING
NEUTRON SPECTROMETERS
NEUTRONS
NUCLEONS
RADIATION DOSES
RADIATION MONITORING
RADIATIONS
SPECTROMETERS