Radiation dose from reentrant electrons

Badhwar, G. D.; Watts, J.; Cleghorn, T. E.

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NASA NTRS · 20040088452

Radiation dose from reentrant electrons

Badhwar, G. D.·Watts, J.·Cleghorn, T. E.

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Abstract

In estimating the crew exposures during an extra vehicular activity (EVA), the contribution of reentrant electrons has always been neglected. Although the flux of these electrons is small compared to the flux of trapped electrons, their energy spectrum extends to several GeV compared to about 7 MeV for trapped electrons. This is also true of splash electrons. Using the measured reentrant electron energy spectra, it is shown that the dose contribution of these electrons to the blood forming organs (BFO) is more that 10 times greater than that from the trapped electrons. The calculations also show that the dose-depth response is a very slowly changing function of depth, and thus adding reasonable amounts of additional shielding would not significantly lower the dose to BFO. Published by Elsevier Science Ltd.

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NASA Center JSC NASA Discipline Radiation Health Radiation Protection Space Flight Extravehicular Activity Electrons Hematopoietic System/radiation effects Radiation Dosage Space Suits Astronauts Radiation Monitoring Human Extraterrestrial Environment Eye/radiation effects Skin/radiation effects Aerospace Medicine Cosmic Radiation Photons

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Badhwar, G. D., Watts, J., Cleghorn, T. E.. 2001-06-01. Radiation dose from reentrant electrons. https://ntrs.nasa.gov/citations/20040088452

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