Detection of low-energy protons using a silicon drift detector

The detection of low-energy protons is a well-known problem in various neutron decay studies. We report first measurements with a silicon drift diode (SDD) using protons with impact energies in the range from 10 to 16 keV. Compared to a standard PIN diode the SDD shows a much improved separation of the proton signal from noise. This detector type initially developed for X-ray spectroscopy will therefore become very useful for proton detection in forthcoming neutron decay experiments. It might also be applied in other projects involving low-energy charged particle detection.