The low earth orbit environment observed using CREAM and CREDO

Area of Science:

• Space physics
• Radiation physics
• Astrophysics

Background:

• The Advanced Photovoltaics & Electronics Experiment Spacecraft has hosted the Cosmic Radiation Environment and Dosimetry (CREDO) experiment since 1994.
• Understanding space radiation is crucial for protecting electronics and astronauts.

Purpose of the Study:

• To measure cosmic ray linear energy transfer spectra and total dose.
• To compare experimental data with predictions from standard models.
• To analyze the effects of spacecraft shielding on radiation measurements.

Main Methods:

• Utilized data from the CREDO experiment on board the Advanced Photovoltaics & Electronics Experiment Spacecraft.
• Collected linear energy transfer spectra data from August 1994 to January 1996.
• Collected total dose data from August 1994 to November 1994.
• Incorporated data from the Cosmic Radiation Environment and Dosimetry experiment (CREAM) flown on STS-63.

Main Results:

• Standard model predictions were found to overestimate the measured linear energy transfer spectra.
• Spacecraft shielding effects were thoroughly investigated and detailed.
• The CREAM experiment demonstrated the penetration of high-energy electrons into the SpaceHab module.

Conclusions:

• Standard models require refinement to accurately predict cosmic ray environments.
• Spacecraft design and shielding are critical factors in mitigating radiation effects.
• Further research is needed to understand high-energy particle penetration in space modules.