Energy degrader technique tor ternary fission studies at LOHENGRIN

The unambiguous identification of light charged particles (LCP), e.g. produced in ternary fission, is a necessary prerequisite for the full understanding of the nature of their formation. To date, mainly two experimental techniques are used to do the job. For one, solid-state detector ΔE-E telescopes combined with time-of-flight measurements; secondly; a mass-separator like LOHENGRIN at Institute Laue-Langevin in combination with an ionization chamber with split anode, the latter serving as ΔE-E telescope. In the first case, the low-energy part of the spectrum cannot be measured, because these LCPs are stopped before reaching the E-detector, while in the second case, the high-energy part of the spectrum remains undetected due to limited electric field settings of the spectrometer. We present, an energy degrader technique that allows the measurement of the entire energy spectrum of even the lightest ternary particles with LOHENGRIN. We discuss the influence of the energy degrader on the measured particle spectra and present results from a Monte Carlo simulation that show how the original energy distributions are reconstructed. Finally, we apply this procedure to experimental data obtained in the reaction 235U (nth, f). (orig.)