The COSPIN Low Energy Telescope (LET) measures the

flux, energy spectra, and elemental composition of solar

energetic particles and low energy cosmic ray nuclei from

hydrogen up to iron in the ~1 MeV/n to ~75 MeV/n energy

range by using a double dE/dX vs. E technique. The

instrument consists of four solid-state detectors, as shown

in the accompanying Figure, which are surrounded by a

cylindrical plastic scintillator anticoincidence shield.

Comprehensive on board particle identifier electronics and

an event priority system enable rare nuclei to be analyzed

in preference to the more common species. Isotope

separation for light nuclei such as He is also achieved.

Further details of the COSPIN instrument are given in

Simpson et al. (1992).