Abstract: The effective quantum efficiency of a metal-channel photomultiplier tube can be increased with an optical system. The optical system can direct incident light from areas of low efficiency on the cathode of the metal-channel photomultiplier tube instead to areas of high efficiency on the cathode. These high-efficiency areas of the cathode can correspond to a position between the dynode structure.

Abstract: A photomultiplier tube (PMT) detector assembly includes a PMT and an analog PMT detector circuit. The PMT includes a photocathode configured to emit an initial set of photoelectrons in response to an absorption of photons. The PMT includes a dynode chain with a plurality of dynodes. The dynode chain is configured to receive the initial set of photoelectrons, generate at least one amplified set of photoelectrons, and direct the at least one amplified set of photoelectrons. The PMT includes an anode configured to receive the at least one amplified set of photoelectrons, with a digitized image being generated based on a measurement of the final amplified set of photoelectrons. The digitized image is corrected by applying an output of the signal measured by the analog PMT detector circuit to the digitized image.

Abstract: A magnetic drum separator is provided. The drum separator includes a drum and a pulley arrangement that rotates the drum. The drum separator includes an end plate coupled to the drive assembly, and the drive assembly rotates the end plate with the drum. The end plate includes a radially oriented slot. A plurality of magnets is disposed in the drum, and the magnets are attached to the end plates and rotatable with the drum. A cam assembly is disposed in the drum and remains stationary during rotation of the drum. The cam assembly includes a cam with a cam track formed therein. The magnets have a cam follower located in the cam track and an end plate follower located in the slot of the end plate. The cam track and the radially oriented slot guide the plurality of magnets to move radially inwards and outwards as the magnets rotate.

Abstract: A rotatable magnet cradle assembly that can be used to separate swarf from a flow of fluid is provided. The cradle of magnets can be rotated a certain amount about a rotational axis from an operational position to a cleaning position. The magnet cradle may include a tube extending between two brackets, a shaft to which the two brackets are attached, and a magnet bar extending through the tube. In the operational position, the magnet provides a magnetic field that attracts swarf to an outer surface of the tube. Once it is desired to clean the assembly, the shaft is rotated to move the two brackets and tube out of the fluid flow and to a position proximate a discharge location, where the magnet bar can be removed from the tube to release the swarf.

Abstract: A photomultiplier tube (PMT) detector assembly includes a PMT and an analog PMT detector circuit. The PMT includes a photocathode configured to emit an initial set of photoelectrons in response to an absorption of photons. The PMT includes a dynode chain with a plurality of dynodes. The dynode chain is configured to receive the initial set of photoelectrons, generate at least one amplified set of photoelectrons, and direct the at least one amplified set of photoelectrons. The PMT includes an anode configured to receive the at least one amplified set of photoelectrons, with a digitized image being generated based on a measurement of the final amplified set of photoelectrons. The digitized image is corrected by applying an output of the signal measured by the analog PMT detector circuit to the digitized image.

Abstract: A rotatable magnet cradle assembly that can be used to separate swarf from a flow of fluid is provided. The cradle of magnets can be rotated a certain amount about a rotational axis from an operational position to a cleaning position. The magnet cradle may include a tube extending between two brackets, a shaft to which the two brackets are attached, and a magnet bar extending through the tube. In the operational position, the magnet provides a magnetic field that attracts swarf to an outer surface of the tube. Once it is desired to clean the assembly, the shaft is rotated to move the two brackets and tube out of the fluid flow and to a position proximate a discharge location, where the magnet bar can be removed from the tube to release the swarf.

Abstract: A magnetic drum separator is provided. The drum separator includes a drum and a pulley arrangement that rotates the drum. The drum separator includes an end plate coupled to the drive assembly, and the drive assembly rotates the end plate with the drum. The end plate includes a radially oriented slot. A plurality of magnets is disposed in the drum, and the magnets are attached to the end plates and rotatable with the drum. A cam assembly is disposed in the drum and remains stationary during rotation of the drum. The cam assembly includes a cam with a cam track formed therein. The magnets have a cam follower located in the cam track and an end plate follower located in the slot of the end plate. The cam track and the radially oriented slot guide the plurality of magnets to move radially inwards and outwards as the magnets rotate.

Abstract: A multi-channel photomultiplier tube (PMT) detector assembly includes a photocathode. The detector assembly includes a first dynode channel including a first set of dynode pathways. The first set of dynode pathways include a plurality of dynode stages configured to receive a first portion of the photoelectrons and direct a first amplified photoelectron current onto a first anode. The detector assembly includes an additional dynode channel including an additional set of dynode pathways. The additional set of dynode pathways includes a plurality of dynode stages configured to receive an additional portion of the photoelectrons and direct an additional amplified photoelectron current onto an additional anode. The detector assembly includes a grid configured to direct the first portion of the photoelectrons to one or more of the first set of pathways and an additional portion of the photoelectrons to one or more of the additional set of pathways.

Abstract: A bias-variant photomultiplier tube (PMT) includes a photocathode that when operating absorbs photons and emits photoelectrons responsive to the absorbed photons. The bias-variant PMTO also includes a plurality of dynodes that receive the photoelectrons emitted by the photocathode. The plurality of dynodes include a first pair of dynodes having a first bias difference and at least a second pair of dynodes having a second bias difference. The second bias difference is greater than the first bias difference. The bias-variant PMTO also includes an anode to receive photoelectrons directed from the plurality of dynodes.

Abstract: A multi-channel photomultiplier tube (PMT) detector assembly includes a photocathode. The detector assembly includes a first dynode channel including a first set of dynode pathways. The first set of dynode pathways include a plurality of dynode stages configured to receive a first portion of the photoelectrons and direct a first amplified photoelectron current onto a first anode. The detector assembly includes an additional dynode channel including an additional set of dynode pathways. The additional set of dynode pathways includes a plurality of dynode stages configured to receive an additional portion of the photoelectrons and direct an additional amplified photoelectron current onto an additional anode. The detector assembly includes a grid configured to direct the first portion of the photoelectrons to one or more of the first set of pathways and an additional portion of the photoelectrons to one or more of the additional set of pathways.

Abstract: A bias-variant photomultiplier tube (PMT) includes a photocathode that when operating absorbs photons and emit photoelectrons responsive to the absorbed photons. The bias-variant PMTO also includes a plurality of dynodes that receive the photoelectrons emitted by the photocathode. The plurality of dynodes include a first pair of dynodes having a first bias difference and at least a second pair of dynodes having a second bias. The second bias difference is greater than the first bias difference. The bias-variant PMTO also includes an anode to receive photoelectrons directed from the plurality of dynodes.