On the west trailing side of the LDEF mission accumulated radiation doses exceeded the annual crew dose limit at shielding of less than 5 cm aluminum. This was influenced by LDEF initial altitude (470 km) and solar minimum conditions for most of the mission.

Cosmic-Ray Heavy Ions
Co, Fe, Mn, Cr and Ti cosmic rays have been discovered near 600 MeV/nucleon. This unexpected result may indicate either a new cosmic ray component or partially ionizing solar flare particles.
The LDEF Cosmic Ray experiments will measure about 20 actinide (Th, U, etc.) nuclei (Z > 65) in the galactic cosmic rays. The current total for previous space flights (Skylab, Ariel and HERO-3) is 3. The LDEF experiments will measure the UH GCR with unprecedented statistics and resolution.

This data will reveal the importance of rapid (explosive) nucleosynthesis for heavy-element production in the galaxy. M0001 was designed to study both galactic and anomalous cosmic rays. The low energy "anomalous" nuclei are now thought to be from the interstellar gas which enters the solar system, becomes partially ionized, and is then accelerated (by shock waves) up to a few tens of MeV. These particles carry information about the interstellar medium and particle acceleration in the solar system. In addition to anomalous cosmic rays, experiment M0002-2 also studies low-energy heavy ions that are trapped in the inner radiation belt. The trapping mechanism for these particles is not understood