In order to improve the maximum counting rate of cryogenic μ-calorimeters used as particle detectors, the application of an external electronic feedback (EEF) system is under development in Genoa, Italy. A description of the experimental setup of such a system and a model which describes the properties of the EEF applied to a current biased μ-calorimeter is reported. The model shows the maximum performance obtainable with such a system, which in principle allows one to improve the detector speed by some orders of magnitude. The model includes also a theoretical noise analysis and the calculation of the intrinsic energy resolution obtained using this kind of system, showing that the EEF does not worsen the energy resolution. The theoretical calculations have been compared with the experimental results obtained in Genoa. The comparison shows a good agreement between theoretical predictions and experimental results. In particular it has been possible to reduce the pulse length, considered as equal to five time constant, from more than 110 ms to less than 4 ms, gaining about a factor of 30 in the detector speed. The corresponding energy resolution with the feedback system is 1.75 times worse than without the feedback system.
ASJC Scopus subject areas