Abstract: A beam injector may include a cathode emitter to emit electrons and an electrode to bias at least a portion of the electrons to remain on the cathode emitter and focus the emitted electrons into an electron beam. The beam injector may also include a resistor coupled between the cathode emitter and the electrode and configured to allow self-regulation of a voltage potential on the electrode based at least in part on a current of the electron beam.

Abstract: The present disclosure relates to a downhole tool that includes a first photon flux detector disposed at a first radial position about a longitudinal axis of the downhole tool that measures a first signal indicative of an x-ray flux of the x-ray photons. The downhole tool also includes a second photon flux detector disposed at a second radial position about the longitudinal axis of the downhole tool that measures a second signal indicative of the x-ray flux of the x-ray photons. Further, the downhole tool includes a controller communicatively coupled to the first photon flux detector and the second photon flux detector that determines a condition associated with the electron beam based at least in part on a relative x-ray flux from the first photon flux detector and the second photon flux detector.

Abstract: A downhole tool may include a high-voltage power supply disposed within a housing to transform input power to the downhole tool from a first voltage to a second voltage greater than the first voltage. The high-voltage power supply may include an array of capacitors, which may include multiple rows of capacitors. The rows of capacitors may be parallel with a symmetric cross section as viewed from an end of the array of capacitors. The high-voltage power supply may also include diodes electrically coupled to the array of capacitors.

Abstract: A downhole tool may include a voltage multiplier within a housing. The voltage multiplier may transform input power to the downhole tool from a first voltage to a second voltage higher than the first. The downhole tool may also include multiple shielding rings surrounding at least the voltage multiplier to reduce electric field stresses within the downhole tool. Additionally, the downhole tool may include an insulator located between the shielding rings and the housing.

Abstract: A apparatus may include a power supply to receive a first voltage potential and output a second voltage potential that is greater than the first voltage potential and a cathode emitter to emit ions in response to application of the second voltage potential. The apparatus may also include a step down transformer to receive the second voltage potential and output a third voltage potential that is less than the second voltage potential. The apparatus may also include a heating element to, in response to application of the third voltage potential, heat the cathode emitter and lower a work function of the cathode emitter.

Abstract: A downhole tool may include a high-voltage power supply disposed within a housing to transform input power to the downhole tool from a first voltage to a second voltage greater than the first voltage. The high-voltage power supply may include an array of capacitors, which may include multiple rows of capacitors. The rows of capacitors may be parallel with a symmetric cross section as viewed from an end of the array of capacitors. The high-voltage power supply may also include diodes electrically coupled to the array of capacitors.

Abstract: The present disclosure relates to a downhole tool that includes a first photon flux detector disposed at a first radial position about a longitudinal axis of the downhole tool that measures a first signal indicative of an x-ray flux of the x-ray photons. The downhole tool also includes a second photon flux detector disposed at a second radial position about the longitudinal axis of the downhole tool that measures a second signal indicative of the x-ray flux of the x-ray photons. Further, the downhole tool includes a controller communicatively coupled to the first photon flux detector and the second photon flux detector that determines a condition associated with the electron beam based at least in part on a relative x-ray flux from the first photon flux detector and the second photon flux detector.

Abstract: A apparatus may include a power supply to receive a first voltage potential and output a second voltage potential that is greater than the first voltage potential and a cathode emitter to emit ions in response to application of the second voltage potential. The apparatus may also include a step down transformer to receive the second voltage potential and output a third voltage potential that is less than the second voltage potential. The apparatus may also include a heating element to, in response to application of the third voltage potential, heat the cathode emitter and lower a work function of the cathode emitter.

Abstract: A downhole tool may include a voltage multiplier within a housing. The voltage multiplier may transform input power to the downhole tool from a first voltage to a second voltage higher than the first. The downhole tool may also include multiple shielding rings surrounding at least the voltage multiplier to reduce electric field stresses within the downhole tool. Additionally, the downhole tool may include an insulator located between the shielding rings and the housing.

Abstract: A beam injector may include a cathode emitter to emit electrons and an electrode to bias at least a portion of the electrons to remain on the cathode emitter and focus the emitted electrons into an electron beam. The beam injector may also include a resistor coupled between the cathode emitter and the electrode and configured to allow self-regulation of a voltage potential on the electrode based at least in part on a current of the electron beam.

Abstract: A downhole tool may include a voltage multiplier within a housing. The voltage multiplier may transform input power to the downhole tool from a first voltage to a second voltage higher than the first. The downhole tool may also include multiple shielding rings surrounding at least the voltage multiplier to reduce electric field stresses within the downhole tool. Additionally, the downhole tool may include an insulator located between the shielding rings and the housing.

Abstract: A downhole tool may include a voltage multiplier within a housing. The voltage multiplier may transform input power to the downhole tool from a first voltage to a second voltage higher than the first. The downhole tool may also include multiple shielding rings surrounding at least the voltage multiplier to reduce electric field stresses within the downhole tool. Additionally, the downhole tool may include an insulator located between the shielding rings and the housing.

Abstract: A radiation generator may include an elongate generator housing having a proximal end and a distal end, a target electrode within the housing at the distal end thereof, a charged particle source within the housing at the proximal end thereof to direct charged particles at the target based upon a first biasing potential, and a field shaping electrode within the housing and adjacent the source to shape a field within the housing. At least one accelerator electrode may be within the housing on an opposite side of the field shaping electrode from the source to accelerate charged particles from the source to the target based upon a second biasing potential different than the first biasing potential. The field shaping electrode may be electrically floating so that the charged particles are directed from the source to the target without applying a biasing potential to the field shaping electrode.

Abstract: Systems, methods, and devices with improved electrode configuration for downhole nuclear radiation generators are provided. For example, one embodiment of a nuclear radiation generator capable of downhole operation may include a charged particle source, a target material, and an acceleration column between the charged particle source and the target material. The acceleration column may include an intermediate electrode that remains floating at a variable potential, being electrically isolated from the rest of the acceleration column.

Abstract: A radiation generator may include an elongate generator housing having a proximal end and a distal end, a target electrode within the elongate generator housing at the distal end thereof, a charged particle source within the elongate generator housing at the proximal end thereof to direct charged particles at the target electrode. A plurality of accelerator electrodes may be spaced apart within the elongate generator housing between the target electrode and the charged particle source to define a charged particle accelerator section. Each accelerator electrode may include an annular portion having a first opening therein, and a frustoconical portion having a base coupled to the first opening of the annular portion and having a second opening so that charged particles from the charged particle source pass through the first and second openings to reach the target electrode.

Abstract: A radiation generator may include an elongate generator housing having a proximal end and a distal end, a target electrode within the elongate generator housing at the distal end thereof, a charged particle source within the elongate generator housing at the proximal end thereof to direct charged particles at the target electrode. A plurality of accelerator electrodes may be spaced apart within the elongate generator housing between the target electrode and the charged particle source to define a charged particle accelerator section. Each accelerator electrode may include an annular portion having a first opening therein, and a frustoconical portion having a base coupled to the first opening of the annular portion and having a second opening so that charged particles from the charged particle source pass through the first and second openings to reach the target electrode.

Abstract: A radiation generator may include an elongate generator housing having a proximal end and a distal end, a target electrode within the housing at the distal end thereof, a charged particle source within the housing at the proximal end thereof to direct charged particles at the target based upon a first biasing potential, and a field shaping electrode within the housing and adjacent the source to shape a field within the housing. At least one accelerator electrode may be within the housing on an opposite side of the field shaping electrode from the source to accelerate charged particles from the source to the target based upon a second biasing potential different than the first biasing potential. The field shaping electrode may be electrically floating so that the charged particles are directed from the source to the target without applying a biasing potential to the field shaping electrode.

Abstract: A method for operating a pulsed neutron generator including an ionizer with an electron emitting cathode and a grid wherein the cathode and grid are disposed in a sealed chamber. At least one of the following is applicable to the ionizer; a distance between the cathode and the grid, a cathode current and/or a potential on the grid are selected such that the ionizer operates at most about one-half the space charge limited current for a grid current selected to provide a predetermined amount of neutron production.

Abstract: Systems, methods, and devices with improved electrode configuration for downhole nuclear radiation generators are provided. For example, one embodiment of a nuclear radiation generator capable of downhole operation may include a charged particle source, a target material, and an acceleration column between the charged particle source and the target material. The acceleration column may include several electrodes shaped such that substantially no electrode material from the electrodes is sputtered onto an insulator surface of the acceleration column during normal downhole operation.

Abstract: A radiation generator includes an insulator, with an ion source carried within the insulator and configured to generate ions and indirectly generate undesirable particles. An extractor electrode is carried within the insulator downstream of the ion source and has a first potential. An intermediate electrode is carried within the insulator downstream of the extractor electrode at a ground potential and is shaped to capture the undesirable conductive particles. In addition, a suppressor electrode is carried within the insulator downstream of the intermediate electrode and has a second potential opposite in sign to the first potential. A target is carried within the insulator downstream of the suppressor electrode. The extractor electrode and the suppressor electrode have a voltage therebetween such that an electric field generated in the insulator accelerates the ions generated by the ion source toward the target.