A gamma-ray spectrometer calibration system comprises a light guide, a photomultiplier tube, a laser, and analysis electronics. The light guide is optically coupled to the scintillation crystal, the laser and the photomultiplier tube, such that the laser can provide reference signals to the photomultiplier tube. In some embodiments, one or more temperature sensors are provided, such that the analysis electronics determine initial settings and adjust the initial settings based on the temperatures measured by the temperature sensors. Additional apparatus, methods, and systems are disclosed.

The method uses the Monte Carlo calculation code MCNP6.1 for: 1) The real modelling of a LaBr.sub.3(Ce) scintillation based radiation detector and a physical structure comprised of multiple sections that contain a large-sized glass fibre filter subdivided into 15 active circular areas. This structure is part of a high volume airborne particulate sampling system; 2) maximizing the position of the LaBr.sub.3(Ce) radiation detector with respect to the above-cited physical structure, in which each of the 15 active areas of the filter contributes towards the calculation of the absolute detection efficiency curve, which is necessary for the quantitative analysis of the natural and artificial radionuclides, each with their own probability of deposition of the aspirated particulate.

This method can be used mainly in automatic radiological monitoring systems that operate for the purposes of radiological/nuclear early alarm, for which the state of the art does not provide the calculation of the absolute detection efficiency with respect to the probability of deposition of the particulate on the filter and, as a result, the accurate measurement of the natural and/or anthropic radionuclides in the aspirated particulate.

The present disclosure discloses a detector device comprising a plurality of detector assemblies. Each detector assembly comprises at least one detection crystal units having a first energy response and those having a second energy response, which are both arranged along a first direction at intervals, each detection crystal unit having a first/second energy response including at least one detection crystals having a first/second energy response arranged along a second direction. The at least one detection crystal units having a first energy response and the at least one detection crystal units having a second energy response are, at least partially, alternatively arranged along the first direction when viewed from an incidence direction of the X-ray. The present disclosure also discloses a dual energy CT system having the detector device and a CT detection method using this system.

According to an embodiment, a radiation detection device includes a scintillator layer, a plurality of detectors, a setting unit, an identifier, and a corrector. The scintillator layer is configured to convert radiation into scintillation light. The detectors are arranged along a first surface facing the scintillator layer to detect light. The setting unit is configured to set one of the detectors as a first detector to be corrected. The identifier is configured to identify, out of the detectors, a second detector that detects a synchronization signal synchronizing with a first signal detected by the first detector. The corrector is configured to correct an energy spectrum of light detected by the first detector on the basis of a second signal serving as the synchronization signal in signals detected by the second detector, the first signal, and characteristic X-ray energy of a scintillator raw material constituting the scintillator layer.

Systems and methods to estimated mean randoms include acquisition of list mode data describing true coincidences and delay coincidences detected by a positron emission tomography scanner during a scan of an object, determination, for each crystal of the positron emission tomography scanner and for each of a plurality of time periods of the scan, of delay coincidences including the crystal based on the list mode data, determination, each crystal, of determine a singles rate associated with each time period based on the delay coincidences determined for the crystal over the time period, determination, for each time period, of determine estimated mean randoms for each of a plurality of pairs of the crystals based on the singles rate associated with the time period for each crystal of the crystal pair, and reconstruction of an image of the object based on the estimated mean randoms for each time period and the detected true coincidences.

Disclosed is a method for spectrally unmixing spectral data originating from a set of spectral sources and including a series of one or more optical spectra. The method can include modeling the spectral data using an endmember matrix and an abundance matrix, the endmember matrix including a set of endmember spectra respectively corresponding to the set of spectral sources, and the abundance matrix indicates an abundance of each endmember spectrum in each spectrum. The method can also include providing external prior spectral information comprising prior endmember information and prior abundance information conveying at least partial prior knowledge about the endmember matrix and the abundance matrix, respectively, and performing a spectral unmixing operation on the spectral data to determine a solution for the endmember and abundance matrices, using the external prior spectral information as input. The method can be employed for calibrating spectral detection systems such as scintillator-based fiber dosimeters.

A method and apparatus to improve the measurement accuracy for ionizing radiation pulses when using large scintillator crystals that absorb their own scintillation light.

A method and system for acquiring spectral information from an energy sensitive nuclear detector is disclosed. The method includes detecting nuclear radiation at a detection device and generating an electronic input pulse indicative of energy deposited in the detection device. The method further includes integrating the electronic input pulse at an integrating device to produce an integrated output signal and digitally sampling the integrated output signal of the integrating device at intervals to produce a stream of digital samples. The method further includes resetting the integrator synchronously with a sampling clock when a limit condition is reached.

A method and apparatus to improve the measurement accuracy for ionizing radiation pulses when using large scintillator crystals that absorb their own scintillation light.

The present invention relates to a rare earth halide scintillating material. The material has a general chemical formula La.sub.1-xCe.sub.xBr.sub.3+y, wherein 0.001x1, and 0.0001y0.1. The rare earth halide scintillating material involved in the present invention has excellent scintillation properties of high light output, high energy resolution, and fast decay.