Abstract: Provided is a detector module for measuring one or more types of radiation, in particular X-ray, gamma ray, or nuclear particle radiation, comprising a detection unit, an analog-to-digital converter, an information processing device, and a memory device for storing the position of the detector module. The detector module comprises at least one light-emitting diode (LED), optically connected with the detection unit for stabilizing the detector unit. Further, the invention provides a stanchion, in particular a portable stanchion, whereby the stanchion comprises a inventive detector module. Yet further, a (wireless) network of detector modules is provided, whereby each detector module is mounted within a stanchion.

Abstract: The invention relates to a neutron detector for detection of neutrons in fields with significant ?- or ?-radiation, comprising a neutron sensitive scintillator crystal, providing a neutron capture signal being larger than the capture signal of 3 MeV ?-radiation, a semiconductor based photo detector being optically coupled to the scintillator crystal, where the scintillator crystal and the semiconductor based photo detector are selected so that the total charge collection time for scintillator signals in the semiconductor based photo detector is larger than the total charge collection time for signals generated by direct detection of ionizing radiation in the semiconductor based photo detector, the neutron detector further comprising a device for sampling the detector signals, a digital signal processing device, means which distinguish direct signals from the semiconductor based photo detector, caused by ?- or ?-radiation and being at least partially absorbed in the semiconductor based photo detector, from lig

Abstract: The invention relates to a detector for measuring nuclear radiation, especially gamma-radiation, comprising a scintillator crystal with a light decay time of less than 100 ns, a silicon drift detector (SDD) for the measurement of both direct hits of low energy radiation and the light, being emitted from the scintillator crystal, the silicon drift detector being mounted between the scintillation crystal and the radiation entry window, a preamplifier, connected to the SDD, electronic devices, being capable of determining the signal rise time of the measured signals and of separating the signals on the basis of said rise time, electronic devices, being capable of separately collecting the energy spectra of SDD and scintillator detection events on the basis of the different rise times.

Abstract: Various screening systems are disclosed, including a system including a radiation detection component, a toxic chemical detection component, a toxic chemical agent sampling component, a bio-threat detection component, a puffer-based bio-threat sampling component, an explosive detection component, and an X-ray based imager, such that it automatically screens mail for the presence of multiple threat agents, such as chemical, biological, radiological, nuclear and explosive threats. An automated sample arm collects a sample when a sampling substrate contacts a portion of the item of mail while there is relative motion between the automated sample arm and the item of mail. The sample is conveyed to a detector and the sampling substrate is regenerated by heating it.

Abstract: A method for linearizing a radiation detector is provided, the method including measuring a pulse height spectrum of a predetermined radiation source, identifying at least one spectrum template for the predetermined radiation source, and determining a linearization function by comparing the measured pulse height spectrum with the at least one identified spectrum template. The at least one spectrum template is a predefined synthesized energy spectrum for the predetermined radiation source and for the corresponding radiation detector. Further, a detector for measuring one or more types of radiation is provided, the detector being adapted for transforming the measured pulse height spectrum in an energy-calibrated spectrum, the transformation including a linearization step, where a linearization function used with the linearization step is determined according to the inventive method.

Abstract: Methods and apparatus for providing a tunable absorption band in a wavelength selective surface are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. The arrangement of surface elements couples at least a portion of the incident electromagnetic radiation between itself and the continuous electrically conductive backing layer, such that the resonant device selectively absorbs incident radiation, and reflects a portion of the incident radiation that is not absorbed.

Abstract: A method for linearizing a radiation detector is provided, the method including measuring a pulse height spectrum of a predetermined radiation source, identifying at least one spectrum template for the predetermined radiation source, and determining a linearization function by comparing the measured pulse height spectrum with the at least one identified spectrum template. The at least one spectrum template is a predefined synthesized energy spectrum for the predetermined radiation source and for the corresponding radiation detector. Further, a detector for measuring one or more types of radiation is provided, the detector being adapted for transforming the measured pulse height spectrum in an energy-calibrated spectrum, the transformation including a linearization step, where a linearization function used with the linearization step is determined according to the inventive method.

Abstract: Provided is a detector module for measuring one or more types of radiation, in particular X-ray, gamma ray, or nuclear particle radiation, comprising a detection unit, an analog-to-digital converter, an information processing device, and a memory device for storing the position of the detector module. The detector module comprises at least one light-emitting diode (LED), optically connected with the detection unit for stabilizing the detector unit. Further, the invention provides a stanchion, in particular a portable stanchion, whereby the stanchion comprises a inventive detector module. Yet further, a (wireless) network of detector modules is provided, whereby each detector module is mounted within a stanchion.

Abstract: A detector for the measurement of radiation, preferably ionizing radiation, includes a medium, means for the conversion of the radiation energy absorbed by the medium into electrical charge, means for digital sampling of the charge signals, means for the determination of a calibration factor K, and means for the stabilization of the output signals of the detector. The medium at least partly absorbs the radiation to be measured. The electric charge is at least partially proportional to the energy of the radiation. The sampling is done preferably with a sampling rate between 1 and 1000 MHz. Further signal processing is digital. The calibration factor K has a fixed relation with respect to the decay time ? of the medium. The output signals of the detector are mainly proportional to the radiation energy, and are stabilized with the help of the calibration factor K.

Abstract: Method for correction of the temperature dependency of a light quantity L emitted by a light emitting diode (LED), being operated in pulsed mode with substantially constant pulse duration tP, and measured in a light detector, using a predetermined parameter X, correlated to the temperature T of the LED in a predetermined ratio, whereby a correction factor K is determined from the parameter X, preferably using a calibration table, especially preferred using an analytic predetermined function, whereby the measured emitted light quantity L is corrected for the temperature contingent fluctuations of the emitted light quantity, whereby the parameter X is determined from at least two output signals of the LED, which are related to each other in a predetermined manner.

Abstract: Various screening systems are disclosed, including a system including a radiation detection component, a toxic chemical detection component, a toxic chemical agent sampling component, a bio-threat detection component, a puffer-based bio-threat sampling component, an explosive detection component, and an X-ray based imager, such that it automatically screens mail for the presence of multiple threat agents, such as chemical, biological, radiological, nuclear and explosive threats. An automated sample arm collects a sample when a sampling substrate contacts a portion of the item of mail while there is relative motion between the automated sample arm and the item of mail. The sample is conveyed to a detector and the sampling substrate is regenerated by heating it.

Abstract: The invention relates to a method for stabilizing the signals generated by a scintillation detector for measuring radiation, especially ionizing radiation, using the radiation which is at least partially absorbed in the detector, said signals depending on the operating temperature of the detector. According to said method, the temperature-dependent calibration factor K is determined from the signal shape of the signals generated by the radiation to be measured itself.