INTERCOMPARISON OF RADIATION MEASUREMENTS ON STS-63

A joint NASA Russia study of the radiation environment inside the Spac e Shuttle was performed on STS-63. This was the second flight under th e Shuttle-Mir Science Program (Phase 1). The Shuttle was launched on 2 February 1995, in a 51.65 degrees inclination orbit and landed at Rem edy Space Center on 11 February 1995, for a total flight duration of 8 .27 days. The Shuttle carried a complement of both passive and active detectors distributed throughout the Shuttle volume. The crew exposure varied from 1962 to 2790 mu Gy with an average of 2265.8 mu Gy or 273 .98 mu Gy/day. Crew exposures varied by a factor of 1.4, which is high er than usual for STS mission. The flight altitude varied from 314 to 395 km and provided a unique opportunity to obtain dose variation with altitude. Measurements of the average east-west dose variation were m ade using two active solid state detectors. The dose rate in the Space hab locker, measured using a tissue equivalent proportional counter (T EPC), was 413.3 mu Gy/day, consistent with measurements made using the rmoluminescent detectors (TLDs) in the same locker. The average qualit y factor was 2.33, and although it was higher than model calculations, it was consistent with values derived from high temperature peaks in TLDs. The dose rate due to galactic cosmic radiation was 110.6 mu Gy/d ay and agreed with model calculations. The dose rate from trapped part icles was 302.7 mu Gy/day, nearly a factor of 2 lower than the predict ion of the AP8 model. The neutrons in the intermediate energy range of 1-20 MeV contributed 13 mu Gy/day and 156 mu Sv/day, respectively. An alysis of data from the charged particle spectrometer has not yet been completed. Copyright (C) 1996 Elsevier Science Ltd