Abstract:
A low-power wireless ionizing radiation measurement system is present that is intended to be used in a wearable dosimeter for occupational radiation monitoring. An apparatus is provided comprising a switching interface, wherein the switching interface alternates between a first switching state and a second switching state. In the first switching state, a radiation-sensitive metal oxide semiconductor capacitor (MOSCAP) is coupled to an external biasing source. In the second switching state, the radiation-sensitive MOSCAP is coupled with reversed polarity relative to the first switching state to a capacitive readout circuit to thereby allow for high-resolution real-time electronic measurement of a radiation- induced capacitance response.
Abstract:
The invention relates to a detector (20) for detecting radon and the decay products thereof in the surrounding air, including in particular aerosols, characterised in that it comprises: a silicon pellet having a PN junction with a deserted area, for transmitting signals under the action of the radiation generated by radon and said decay products; a passivation layer (22) covering said silicon pellet and enabling the operation of said detector in open air; and a conducting layer (24) covering the passivation layer and defining a radionuclide collecting electrode. The invention also relates to a detection device including said detector.
Abstract:
Methods and apparatus are described for marine asset security and tracking (MAST). A method includes transmitting identification data, location data and environmental state sensor data from a radio frequency tag. An apparatus includes a radio frequency tag that transmits identification data, location data and environmental state sensor data. Another method includes transmitting identification data and location data from a radio frequency tag using hybrid spread-spectrum modulation. Another apparatus includes a radio frequency tag that transmits both identification data and location data using hybrid spread-spectrum modulation.
Abstract:
Methods and apparatus are described for space charge disometers for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method included arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.
Abstract:
A real time radiation dosimeter includes a first electrode and a second electrode, such as cathode and anode electrodes. The second electrode is based on carbon nanomaterials, such as carbon nanotubes bucky paper, carbon nanotubes forest and graphene film. The dosimeter is connected to an electrometer, able to apply a bias voltage between the electrodes and to measure the collected charge. The manufactured detectors display an excellent linear response to dose. The dosimeter with nanotubes forest is able to collect charge also to zero voltage, allowing in vivo applications. The use of nanomaterials allows a miniaturized version of dosimeters.
Abstract:
The invention relates to a quality assurance method for a radiotherapy apparatus (10) employing a photon beam (20) directed onto an object or patient (30), comprising the following steps: the object or patient (30) is galvanically isolated from a reference potential; a picoammeter (60) is connected between the object or patient (30) and the reference potential; the photon beam (20) is directed onto the object or patient (30); and the electrical charge (Q) created in the object or patient (30) and/or the electrical current (I) flowing between the object or patient (30) and the reference potential is measured by means of the picoammeter (60). The invention also relates to an apparatus suitable for carrying out this method.
Abstract:
Methods and apparatus are described for space charge disometers for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method included arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.
Abstract:
A radiotherapy dose rate monitor system includes an electrode 220 configured to be impinged by radiotherapy radiation, and a current measurement circuit 305 configured to measure a current through the electrode. An emission of secondary electrons emitted from the electrode provides a majority of current through the electrode.
Abstract:
A method for measuring radiotherapy doses, in particular on a subject undergoing radiotherapy or other treatments with ionizing radiations, does not require any voltage applied to the subject nor the radiation of a signal collecting sensor, and it is capable of providing a measurement of absolute type, and on this regard it comprises the steps of: electrically insulating the subject during the radiotherapy treatment; applying at least one electrode to the subject, or connected to an amplifier with a system for acquiring the signal outgoing from the amplifier; detecting, by means of said at least one electrode, the voltage pulse produced during the radiotherapy treatment and deriving from the ionization secondary electrons set into motion and/or by the loaded net charge induced in the subject; converting said voltage pulse into a value of charge induced by the treatment in the subject; and determining the dose of ionizing radiations received by the subject by means of a processing system which uses the above-mentioned value of the induced charge, the energy spectrum of the incident beam of ionizing radiations and the contact surface of said incident beam on the subject.
Abstract:
L'invention concerne une méthode d'assurance qualité d'un appareil de radiothérapie (10) par un faisceau de photons (20) dirigés vers un objet ou un patient (30), comportant les étapes suivantes : on isole galvaniquement l'objet ou le patient (30) d'un potentiel de référence; on relie un pico-ampèremètre (60) entre l'objet ou le patient (30) et le potentiel de référence; on dirige le faisceau de photons (20) vers l'objet ou le patient (30); on mesure au moyen du pico-ampèremètre (60) la charge électrique (Q) prenant naissance dans l'objet ou le patient (30) et/ou le courant électrique (I) circulant entre l'objet ou le patient (30) et le potentiel de référence. L'invention se rapporte également à un appareil adapté à l'exécution de cette méthode.