Signals induced by charge-trapping in EDELWEISS FID detectors: Analytical modeling and applications

The EDELWEISS-III direct dark matter search experiment uses cryogenic HP-Ge detectors Fully covered with Inter-Digitized electrodes (FID). They are operated at low fields (< 1 V/cm), and as a consequence charge-carrier trapping significantly affects both the ionization and heat energy measurements. This paper describes an analytical model of the signals induced by trapped charges in FID detectors based on the Shockley-Ramo theorem. It is used to demonstrate that veto electrodes, initially designed for the sole purpose of surface event rejection, can be used to provide a sensitivity to the depth of the energy deposits, characterize the trapping in the crystals, perform heat and ionization energy corrections and improve the ionization baseline resolutions. These procedures are applied successfully to actual data

Facilities of different methods of automatic recognition of sleep stages

&lt;p&gt;The gole of the research is to consider the information content in application of different fractal methods of deterministic chaos to the automated recognition of sleep phases in computer electroencephalogram (EEG). The Hurst normalized range method, the method of calculating of Grassberger — Procaccia correlation integral and the approximated entropy method are used during the research. The research reveals that a hypnogram can be obtained. It’s possible if appropriate parameters of the methods indicated above are used, as well as the necessary normalization of the original data and averaging the results. A hypnogram has a total coincidence of defned sleep phases for half of the epochs which are recorded on EEG. Current methods of automatic recognition of sleep stages based on the deterministic chaos allow to reduce signifcantly the time of interpretation of polysomnographic recording and reduce the number of channels through which parameters of sleep are registrated.&lt;/p&gt