en 
The VACUTEC proportional counter probe (hereinafter referred as to “PCP”) is based upon a large volume gas-filled detector of high sensitivity towards photon radiation. As a stationarily operated device, it is provided to monitor environmental radiation. It features capability to perform quasispectroscopy by comparing continuously updated pulse height spectra with a basis set of response vectors to be considered as discrete probability distributions containing the local radiometric fingerprint. The local radiometric fingerprint represents the contamination-free situtation locally.
To be more precisely, a current spectrum is deconstructed into a natural and a non-natural part by deconvoluting, whereby a reliable differentiation is obtained between the local background and contributions of artificial origin. The PCP responds to present contamination by an increase of rate components, which add up to exactly the overall count rate.
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