Influence of the plasma effects on the energy spectra

Proton and helium energy spectra are observed under influence of plasma effects in a silicon detector. For heavier particles, it is shown that the plasma density along the trajectory of the incident particles into silicon is more serious than the length of its ionized track for the pulse height defect. The pulse height defect and the width of the spectra are proportional to the inverse square of the applied field 1/E2, and the electric field erosion into plasma plays an important role in the plasma effects. (orig.)