Abstract: A mixed halide scintillator material including a fluoride is disclosed. The introduction of fluorine reduces the hygroscopicity of halide scintillator materials and facilitates tuning of scintillation properties of the materials.

Abstract: Disclosed are a method of growing a rare-earth oxyorthosilicate crystal and a crystal grown using the method. A melt is prepared by melting a first substance including at least one rare-earth element and a second substance including at least one element from group 7 of the periodic table. A seed crystal is brought into contact with the surface of the melt and withdrawn to grow the crystal.

Abstract: A method and device for improving the optical performance (such as time resolution) of scintillation detectors using the optical bleaching technique are disclosed. Light of a selected wavelength is emitted by a light source into a scintillator. The wavelength is selected to meet the minimum energy requirement for releasing of charge carriers captured by the charge carrier traps in the scintillation material. Trap-mediated scintillation components are thus reduced by optical bleaching and the optical performance of the scintillator crystal and the detector is enhanced.

Abstract: A method of growing a rare-earth oxyorthosilicate crystal, and crystals grown using the method are disclosed. The method includes preparing a melt by melting a first substance including at least one first rare-earth element and providing an atmosphere that includes an inert gas and a gas including oxygen.

Abstract: A method for making a rare-earth oxyorthosilicate scintillator single crystal includes growing a single crystal from a melt of compounds including a rare-earth element (such as Lu), silicon and oxygen, a compound including a rare-earth activator (such as Ce), and a compound of a Group-7 element (such as Mn). The method further includes selecting an scintillation performance parameter (such as decay), and based on the scintillation performance parameter to be achieved, doping activator and Group-7 element at predetermined levels, or relative levels between the two, so as to achieve stable growth of the single-crystalline scintillator material from the melt.

Abstract: A pulling head for a crystal growth furnace. The pulling head includes a servomotor and a rotatable housing attached to the servomotor, wherein the housing includes first, second, third and fourth housing magnets. The pulling head also includes a shaft attached to a scale and a connection device having first and second connection magnets. The first connection magnet is arranged between the first and second housing magnets to generate first and second magnetic repulsion forces and the second connection magnet is arranged between the third and fourth housing magnets to generate third and fourth magnetic repulsion forces. A rotation coupling is attached between the shaft and the connection device wherein the scale weighs the shaft, rotation coupling and the connection device. The servomotor rotates the housing and rotation of the housing is transmitted by the magnetic repulsion forces to the connection device to rotate the connection device.

Abstract: A cantilever device for extending capacity of a scale used in a crystal growth apparatus having a pulling head wherein upward movement of a support column in the pulling head decreases a weight measured by the scale. The device includes a horizontal arm having first and second brackets, wherein the first bracket is attached to the pulling head. The device also includes a plate that extends through openings in the first and second brackets, wherein the plate includes a contact end and a free end. Further, the device includes a flexible element attached between the arm and the plate to form a pivot to enable rotation of the plate. A load is positioned on the plate wherein the load causes rotation of the plate about the pivot to cause upward movement of the contact end to move the support column upward to decrease weight measured by the scale.

Abstract: A growth chamber or a Czochralski crystal growth station has one or more re-sealable caps that are inserted into the chamber body. An O-ring seals the cap within its mating portion of the chamber body. The re-sealable caps facilitate re-use of the chamber body for a future crystal growth cycle.

Abstract: Disclosed herein is a method comprising discharging a slurry from a vessel to a conduit; where the slurry comprises a liquid and a composition comprising at least two materials having different densities-a first material having a higher density and a second material having a lower density than that of the first material; creating a surge in velocity in slurry flow as it is transported through the conduit; separating the first material from the second material; where the first material is disposed on an inner surface of the conduit and where the second material flows through the conduit to a container; and removing the first material from the inner surface of the conduit.

Abstract: The use of the effect of crystallographic axis orientation on the effectiveness in annealing in multiple atmospheres and chemical compositions of lutetium oxyorthosilicate crystals and other scintillator crystals is disclosed. By controlling axis orientation an favorable annealing condition can be selected to repair both internal interstitial and vacancy defects through the crystal lattice. Axis orientation can be further utilized to control the uniformity of surface finish of chemically etched crystal.

Abstract: A halide material, such as scintillator crystals of LaBr3:Ce and SrI2:Eu, with a passivation surface layer is disclosed. The surface layer comprises one or more halides of lower water solubility than the scintillator crystal that the surface layer covers. A method for making such a material is also disclosed. In certain aspects of the disclosure, a passivation layer is formed on a surface of a halide material such as a scintillator crystal of LaBr3:Ce of SrI2:Eu by fluorinating the surface with a fluorinating agent, such as F2 for LaBr3:Ce and HF for SrI2:Eu.

Abstract: A Czochralski process (“CZ”) crystal growth method and furnace having a heater capable of generating a heating zone, a crucible within the heating zone and capable of retaining a volume of molten crystal growth material forming a melt line oriented in a designated position within the heating zone, a seed growth rod retractable from the crucible with a rod retraction mechanism, for forming a crystal boule thereon proximal the melt line from the molten crystal growth material. The furnace causes relative movement between the crucible and heating zone as the crystal boule is retracted, so that the melt line is maintained in the designated position within the heating zone. In some embodiments relative movement is based at least in part on sensed weight of the growing crystal boule. In other embodiments the crucible growth rod retraction mechanism are fixed relative to each other by a gantry.

Abstract: A method and device for improving the optical performance (such as time resolution) of scintillation detectors using the optical bleaching technique are disclosed. Light of a selected wavelength is emitted by a light source into a scintillator. The wavelength is selected to meet the minimum energy requirement for releasing of charge carriers captured by the charge carrier traps in the scintillation material. Trap-mediated scintillation components are thus reduced by optical bleaching and the optical performance of the scintillator crystal and the detector is enhanced.

Abstract: A mixed halide scintillator material including a fluoride is disclosed. The introduction of fluorine reduces the hygroscopicity of halide scintillator materials and facilitates tuning of scintillation properties of the materials.

Abstract: A lid for a crystal growth chamber crucible is constructed by forming arcuate sector-shaped portions and coupling them in abutting relationship, for example by welding, to form an annular profile fabricated lid. The arcuate sector-shaped portions may be formed and removed from a lid fabrication blank with less waste than when unitary annular lids are formed and removed from a similarly sized fabrication blank. For example, the sector-shaped portions may be arrayed in an undulating pattern on the fabrication sheet.

Abstract: A method for fabricating a detector or light guide using laser technology. The method yields a detector component such as a scintillator, light guide or optical sensor which provides for the internal manipulation of light waves via the strategic formation of micro-voids to enhance control and collection of scintillation light, allowing for accurate decoding of the impinging radiation. The method uses laser technology to create micro-voids within a target media to optically segment the media. The micro-voids are positioned to define optical boundaries of the optically-segmented portions forming virtual resolution elements within the scintillator. Each micro-void is formed at its selected location using a laser source. The laser source generates and focuses a beam of light into the target media sequentially to form the micro-voids. The laser beam ablates the media at the focal point, thereby yielding the micro-void.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: A device for detecting ionizing radiation includes a radiation interaction region configured to generate light in response to an interaction with the ionizing radiation, an optical gain medium region in optical communication with the radiation interaction region and configured to amplify the light, and an energy source coupled to the optical gain medium region and configured to maintain a state of population inversion in the optical gain medium region. The optical gain medium region has an emission wavelength that corresponds with a wavelength of the light generated by the radiation interaction region.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.