33 results about "Gamma ray spectrometer" patented technology

A gamma ray detector (50) comprises a plastic scintillation body (52) arranged to receive incident gamma rays to be detected. Photons are generated in response to the gamma rays by excitation and de-excitation processes in the scintillation body. The photons are detected using at least one photodetector (56) which generates an output signal representative of the energy of the gamma rays. The scintillation body has a detection surface to receive the gamma rays and a thickness in a direction substantially orthogonal to the detection surface that is not greater than 5 cm. Deconvolution techniques can be used to improve the output signal; the thinness of the scintillation body allows sufficiently accurate results to be obtained that individual isotopes can be readily identified. The detector can be usefully employed in portal radiation monitors.

The intrinsic background of a gamma ray spectrometer is significantly reduced by surrounding the scintillator with a second scintillator. This second (external) scintillator surrounds the first scintillator and has an opening of approximately the same diameter as the smaller central scintillator in the forward direction. The second scintillator is selected to have a higher atomic number, and thus has a larger probability for a Compton scattering interaction than within the inner region. Scattering events that are essentially simultaneous in coincidence to the first and second scintillators, from an electronics perspective, are precluded electronically from the data stream. Thus, only gamma-rays that are wholly contained in the smaller central scintillator are used for analytic purposes.

A calibration source comprises a radioactive material comprising a radioactive isotope having a decay transition associated with emission of a radiation particle and gamma-rays having a known energy and a solid-state detector, arranged to receive radiation particles emitted from the radioactive material. A gating circuit is coupled to the solid-state detector and is operable to generate a gating signal in response to detection of a radiation particle in the solid-state detector. The gating signal may thus be used as an indicator that an energy deposit in a nearby gamma-ray spectrometer is associated with a decay transitions in the radioactive isotope. Since these energy deposits are of a known energy, they can be used as reference points to calibrate the spectrometer response. Thus with calibration sources according to embodiments of the invention, spectral stabilization may be performed in real time and in parallel with obtaining a spectrum of observed signal events.

A calibration source for a gamma-ray spectrometer is provided, comprising a scintillator body having a cavity in which a radioactive material is received. A scintillator body may be cuboid and the cavity may be a hole drilled into the scintillator body. The radioactive material comprises an isotope having a decay transition associated with emission of a radiation particle and a gamma-ray of known energy. A photodetector is optically coupled to the scintillator body and arranged to detect scintillation photons generated when radiation particles emitted from the radioactive material interact with the surrounding scintillator. A gating circuit is arranged to receive detection signals to generate corresponding gating signals for a data acquisition circuit of an associated gamma-ray spectrometer to indicate that gamma-ray detections in the gamma-ray spectrometer occurring within a time window defined by the gating signal are associated with a decay transition in the radioactive isotope.

A combined thermal neutron detector and gamma-ray spectrometer system, including: a detection medium including a lithium chalcopyrite crystal operable for detecting thermal neutrons in a semiconductor mode and gamma-rays in a scintillator mode; and a photodetector coupled to the detection medium also operable for detecting the gamma rays. Optionally, the detection medium includes a 6LiInSe2 crystal. Optionally, the detection medium comprises a compound formed by the process of: melting a Group III element; adding a Group I element to the melted Group III element at a rate that allows the Group I and Group III elements to react thereby providing a single phase I-III compound; and adding a Group VI element to the single phase I-III compound and heating; wherein the Group I element includes lithium.

A combined thermal neutron detector and gamma-ray spectrometer system, including: a first detection medium including a lithium chalcopyrite crystal operable for detecting neutrons; a gamma ray shielding material disposed adjacent to the first detection medium; a second detection medium including one of a doped metal halide, an elpasolite, and a high Z semiconductor scintillator crystal operable for detecting gamma rays; a neutron shielding material disposed adjacent to the second detection medium; and a photodetector coupled to the second detection medium also operable for detecting the gamma rays; wherein the first detection medium and the second detection medium do not overlap in an orthogonal plane to a radiation flux. Optionally, the first detection medium includes a 6LiInSe2 crystal. Optionally, the second detection medium includes a SrI2(Eu) scintillation crystal.

An apparatus is described. The apparatus comprising a gamma-ray spectrometer arranged to receive gamma-rays from a calibration source, the gamma-ray spectrometer comprising: a scintillator material optically coupled to two or more photomultipliers, the two or more photomultipliers being arranged to detect photons generated in the scintillator material associated with gamma-ray interactions between the scintillator material and gamma-rays received from the calibration source, wherein the two or more photomultipliers are operable to output respective detection signals associated with the gamma-ray interactions; the apparatus further comprising: a switch coupled to receive the respective detection signals from the two or more photomultipliers and operable to select detection signals from one of the two or more photomultipliers; and a stabilization circuit coupled to the switch and operable to receive the selected detection signal of the respective photomultiplier and to stabilize the gain of the photomultiplier that output the selected detection signal based on the detection signals.

The invention relates to X-ray spectral analysis and can be used for control of radiation spectra of X-ray generators as well as for analysis of elemental chemical composition and atomic structure of the specimens by measuring their absorption spectra. The X-ray spectrometer comprises at least one dispersing prism element, means of translation of the dispersing element relative to an X-ray beam, a refracted radiation detector and measuring tools for angle positioning of the dispersing element and the refracted radiation detector. The main distinction of the claimed spectrometer is that it contains an additional radiation detector, means to install it downstream the radiation reflected from the refracting surface of the dispersing element and measuring tools for its angle position in relation to the primary X-ray beam. The dispersing element is made of diamond, or beryllium, lithium hydride or boron carbide. The claimed spectrometer scheme provides a multiple increase of spectral measurements accuracy within the energy range up to 100 keV and possibility of pulse spectra calibration.

The invention relates to a method and a system for detecting the accuracy of a gamma ray spectrometer. The method comprises the following steps of exploring test samples under the scheduled test environment by utilizing the gamma ray spectrometer to obtain exploration data; analyzing the content of elements explored by the gamma ray spectrometer from the test samples according to the obtained exploration data; and comparing the content of the elements with the standard value of the content of the elements in the test samples and judging whether the gamma ray spectrometer has the element exploration capability or not according to the comparison result. The system comprises the gamma ray spectrometer, a data acquisition device, a data analysis device, a comparison device and a display device. The method and the system of the invention can acquire the capability for exploring the elements before the gamma ray spectrometer is used for the fields of lunar exploration and the like so as to guarantee the accuracy of the data when the gamma ray spectrometer is used.

The invention discloses a high-purity germanium gamma ray spectrometer with wide-energy anti-compton electric refrigeration, which comprises a bottom plate I. A supporting plate I is arranged above the bottom plate I. The top of the supporting plate I is provided with a locking mechanism. The top of the locking mechanism is provided with a refrigerating device. The inside of the refrigerating device is provided with a detector. The top of the refrigerating device is provided with a lead chamber. The middle position of the top end of the bottom plate I is provided with a mounting plate I. The middle position of the bottom of the supporting plate I is provided with a mounting plate II. One side of the mounting plate I is provided with a spectrum analysis device. The top end of the mounting plate I is provided with two sets of fixing blocks I. The inside of each fixing block I is provided with a semi-tooth gear I. Each semi-tooth gear I is connected with one end of a connecting rod I. Theother end of each connecting rod I is provided with a movable block. The upper end of each movable block is provided with a second connecting rod II. The upper end of each connecting rod II is provided with a semi-tooth gear II. The high-purity germanium gamma ray spectrometer with the wide-energy anti-compton electric refrigeration has the beneficial effects that the height of the support plateII can be adjusted according to the height of a worker, so that the worker can conveniently adjust and replace the refrigerating device.

A system and method for additively manufacturing a component including features for part identification are provided. The method includes selectively depositing a contrast agent on a cross sectional layer to define a component identifier of the component and directing energy from an energy source onto the contrast agent to fuse the contrast agent and the cross sectional layer. The contrast agent may be an x-ray emission contrast agent that is read using an x-ray emission spectroscopy method, an infrared contrast agent that is read using an infrared camera or an infrared scanner, or a radioactive contrast agent that is read using a gamma ray spectrometer.