Various techniques are provided to detect the direction and location of one or more radiation sources. In one example, a system includes a plurality of radiation detectors configured to receive radiation from a radiation source. A first one of the radiation detectors is positioned to at least partially occlude a second one of the radiation detectors to attenuate the radiation received by the second radiation detector. The system also includes a processor configured to receive detection information provided by the first and second radiation detectors in response to the radiation, and determine a direction of the radiation source using the detection information. A modular system including gamma radiation detectors and neutron radiation detectors and related methods are also provided. In some cases, radiation source type may be determined in addition to or separate from radiation source direction.

The present invention relates to a method for extending the lifespan of rhodium measuring devices. To this end, the method comprises the steps of: measuring current signals, expressed in amperes, which are induced by electrons emitted as a result of rhodium, in each rhodium measuring device, undergoing beta decay as a result of absorbing neutrons (S10); on the basis of the current signals, and by using a CECOR program, calculating, for each rhodium burnup, respective positional output values of the individual rhodium measuring devices (S20); calculating, for each rhodium burnup, an optimal output value for all positions (S30); determining a W′ correction constant, or a change in an exponent of an approximate expression of the sensitivity of the rhodium measuring devices (S40); calculating, for each rhodium burnup, respective positional output values of the individual rhodium measuring devices, and checking same by carrying out a comparative analysis between same and the respective positional output values of the rhodium measuring devices, calculated in S20 (S50); and extending the lifespan of usage of the rhodium measuring devices by applying the W′ correction constant, or the exponent of the approximate expression of sensitivity, at the time point when ⅔ or more of the rhodium in the rhodium measuring devices is burned up (S60).

The present invention relates to a method for extending the lifespan of rhodium measuring devices. To this end, the method comprises the steps of: measuring current signals, expressed in amperes, which are induced by electrons emitted as a result of rhodium, in each rhodium measuring device, undergoing beta decay as a result of absorbing neutrons (S10); on the basis of the current signals, and by using a CECOR program, calculating, for each rhodium burnup, respective positional output values of the individual rhodium measuring devices (S20); calculating, for each rhodium burnup, an optimal output value for all positions (S30); determining a W′ correction constant, or a change in an exponent of an approximate expression of the sensitivity of the rhodium measuring devices (S40); calculating, for each rhodium burnup, respective positional output values of the individual rhodium measuring devices, and checking same by carrying out a comparative analysis between same and the respective positional output values of the rhodium measuring devices, calculated in S20 (S50); and extending the lifespan of usage of the rhodium measuring devices by applying the W′ correction constant, or the exponent of the approximate expression of sensitivity, at the time point when ⅔ or more of the rhodium in the rhodium measuring devices is burned up (S60).

An excore detector assembly for measuring flux outside of a nuclear reactor core. The excore detector assembly includes a housing and at least one self-powered detector inside the housing for measuring flux generated by the nuclear reactor core. The at least one self-powered detector includes a sheath, a detector material section inside the sheath, an insulator between the sheath and the detector material, and a flux signal output line.

A radiation detector (100) includes an insulating substrate (110), which includes a material that undergoes a change in an electrical property when subjected to ionizing radiation. A conductive film (112) is disposed in relation to a surface of the substrate. The conductive film (112) has a resistance that is a function of a state of the electrical property. A resistance measuring device measures resistance across the conductive film (112). The resistance measured by the resistance measuring device indicates an amount of ionizing radiation to which the substrate (110) has been subjected. In a method of determining exposure to a type of radiation, a boron nitride substrate is exposed to a radiation environment. A resistance is measured across a conductive film disposed in relation to the boron nitride substrate. Radiation exposure is calculated as a function of the resistance.

A radiation detector (100) includes an insulating substrate (110), which includes a material that undergoes a change in an electrical property when subjected to ionizing radiation. A conductive film (112) is disposed in relation to a surface of the substrate. The conductive film (112) has a resistance that is a function of a state of the electrical property. A resistance measuring device measures resistance across the conductive film (112). The resistance measured by the resistance measuring device indicates an amount of ionizing radiation to which the substrate (110) has been subjected. In a method of determining exposure to a type of radiation, a boron nitride substrate is exposed to a radiation environment. A resistance is measured across a conductive film disposed in relation to the boron nitride substrate. Radiation exposure is calculated as a function of the resistance.

Devices, systems, and methods of using one or more memristors as a radiation sensor are enabled. A memristor can be attractive as a sensor due to its passive low power characteristics. Medical and environment monitoring are contemplated use cases. Sensing radiation as part of a security system (at an airport for example) and screening food for radiation exposure are also possible uses. The memristor as a radiation sensor may possibly provide an inexpensive and easy alternative to personal thermoluminescent dosimeters (TLD). Memristor devices with high current and low power operation may be attached with wearable plastic substrates. An example device includes two metal strips with a 50 μm thick layer of TiO.sub.2 memristor material. The device may be made large relative to traditional memristors which are nanometers in scale but its increased thickness can significantly increase the probability of radiation interaction with the memristor material.

A wide area cosmogenic neutron sensor is used for detecting moisture within a measurement surface. A neutron detector is positioned on a stand structure holding the detector above a measurement surface. A moderator material and neutron shield are positioned around at least a portion of the neutron detector. The neutron shield substantially covers an entirety of a bottom of the neutron detector and is not positioned on a top side of the neutron detector. Wide area cosmogenic neutrons propagating from the measurement surface travel through an air space before arriving at the moderated neutron detector.

A wide area cosmogenic neutron sensor is used for detecting moisture within a measurement surface. A neutron detector is positioned on a stand structure holding the detector above a measurement surface. A moderator material and neutron shield are positioned around at least a portion of the neutron detector. The neutron shield substantially covers an entirety of a bottom of the neutron detector and is not positioned on a top side of the neutron detector. Wide area cosmogenic neutrons propagating from the measurement surface travel through an air space before arriving at the moderated neutron detector.

A fissile neutron detection system includes a neutron moderator and a neutron detector disposed proximate such that a majority of the surface area of the neutron moderator is disposed proximate the neutron detector. Fissile neutrons impinge upon and enter the neutron moderator where the energy level of the fissile neutron is reduced to that of a thermal neutron. The thermal neutron may exit the moderator in any direction. Maximizing the surface area of the neutron moderator that is proximate the neutron detector beneficially improves the reliability and accuracy of the fissile neutron detection system by increasing the percentage of thermal neutrons that exit the neutron moderator and enter the neutron detector.