Detection of true Gaussian shaped pulses at high count rates

A new true Gaussian digital shaper of detector pulses is analised for applications with soft X-ray spectrometers at the highest count rates. The true Gaussian shaper allows for shaping detector pulses into a symmetrical form which width can be considerably less than the rise time of the input pulses. Therefore, the dead time of the true Gaussian shaper can be noticeably reduced in regards to that of trapezoidal shaper. Less dead time provides a higher count rate of the true Gaussian pulses. The true Gaussian shaper is compared to the standard trapezoidal shaper in terms of count rate, amplitude resolution and biasing the output shaped pulses in a wide range of the input count rates. The maximal output count rate of the true Gaussian shaper has been found to exceed the rate of the trapezoidal shapers in several times. The true Gaussian shaper provides biasing-free measurements of pulse amplitudes with better resolution than that provided by the trapezoidal shapers at high count rates. The tests have been performed by modeling the output signals of silicon drift detector (SDD) H7 VITUS equipped with AXAS-D pre-amplifier developed by KETEK GmbH for measurements of soft X-ray spectra at high count rates.