Abstract: Particle analyzers having scintillation counters are provided. Particle analyzers of interest include a flow cell for transporting particles in a flow stream, a light source for irradiating a particle in the flow stream at an interrogation point, a particle-modulated light detector for detecting light from the interrogation point, and a scintillation counter for assessing particle radioactivity. In embodiments, the scintillation counter is positioned within the flow cell and configured generate particle radioactivity data that may be associated with a given particle in a plurality of particles. Methods and non-transitory computer readable storage media for practicing the invention are also provided.

Abstract: The present disclosure describes optically enhanced high resolution image guides having a high core to cladding area ratio with reduced spectral transmission loss and reduced cross talk while maintaining high resolution and high transmission.

Abstract: The present disclosure is directed to a robust system and method that delivers precise volumes of fluid, including weight-based fluid volumes (e.g., as prescribed by a medication dose), avoids the expenses and complexity associated with having multiples devices for cutaneous, subcutaneous, and oral administration, avoids the time-consuming cleaning associated with internal component contamination, and avoids the expenses and complications associated with human and mechanical error and failure, of prior art mass fluid delivery systems and methods.

Abstract: A fluid testing cassette may comprise a microfluidic channel having a constriction and a micro-fabricated integrated sensor within the constriction. In one implementation, the constriction is less than or equal to 30 ?m. In one implementation, the cassette further comprises a nozzle connecting the microfluidic channel to the discharge reservoir, wherein a thermal resistor expels fluid within the microfluidic channel into the discharge reservoir.

Abstract: Radiation detectors and methods of using the radiation detectors that provide a route for surface decontamination during use are described. The detectors utilize light illumination of an internal surface during use. Light is in the longer UV to near-infrared spectra and desorbs contamination from internal surfaces of radiation detectors. The methods can be carried out while the detectors are in operation, preventing the appearance of the negative effects of radioactive and non-radioactive contamination during a detection regime and following a detection regime.

Abstract: A watching assistance system that assists watching over a subject on a bed includes an image acquisition unit configured to acquire an image captured by an imaging device, a criterion storage in which a criterion for determining a dangerous state are previously set for each of a plurality of determination regions set based on a region of the bed in the image, a detector configured to detect the subject from the image acquired by the image acquisition unit, a state recognition unit configured to recognize a state of the subject detected by the detector, a determination unit configured to determine a danger degree of the state of the subject recognized by the state recognition unit using the criterion for the determination region corresponding to a position at which the subject is detected by the detector, and an output unit configured to provide notification according to the danger degree determined by the determination unit.

Abstract: The present invention relates to a sensor device for detecting dose of radiation received at the sensor device, the sensor device comprising a flexible body having a cross-section being comparatively small relative to the length of the device, a cladding at the flexible body, the cladding converting incoming radiation into visible light, and an optical shape sensing device disposed within the flexible body and configured to determine a shape of the flexible instrument relative to a reference, the shape sensing device configured to collect information based on its configuration to map an intraluminal structure during a procedure. The present invention further relates to a radiation therapy system including such a sensor device and a method of operating a radiation therapy system including such a sensor device.

Abstract: An alpha ray observation device and an alpha ray observation method are provided that can correctly evaluate a signal derived from alpha rays. The alpha ray observation device according to an embodiment includes a device housing 10, an incident window 2, a condenser 3, an optical path changer 4, and a first optical detector 5. The device housing 10 is provided with an opening. The incident window 2 is provided at the opening, and can block beta rays. Emitted light originated by alpha rays caused from the measurement object set outside of the device housing 10 enters the inside of the device housing 10 through the incident window 2 with beta rays being blocked, and is condensed by the condenser 3, and the optical path is changed by the optical path changer 4, and subsequently the light is detected by the first optical detector 5. The first optical detector 5 outputs a signal according to the amount of detected light.

Abstract: A radiation detecting system, including: plastics scintillators juxtaposed to form at least one pair of contiguous plastics scintillators; a photomultiplier associated with each plastics scintillator to provide an electrical signal representative of the light signal generated in the plastics scintillator; a calculator connected to the photomultipliers and configured to: detect pulse coincidences between two electrical pulses provided by the photomultipliers associated with a pair of contiguous plastics scintillators; for each pulse coincidence, determine the time offset between the coincidence pulses relative to the pulse having the greatest amplitude taken as a zero reference; determine the number of pulse coincidences the time offset of which is included in a time offset window.

Abstract: The present invention provides a flow cell that can be used to improve the linear detection range of a radio-detector. The flow cell of the present invention is simple and cost-effective to set up and provides technical advantages over methods known in the prior art, as set out in more detail hereunder. The present invention also provides a method to determine the RCP of a radioactive composition making use of said flow cell, and a HPLC system comprising said flow cell.

Abstract: An optical liquid sensor utilizing a light source, fiber optic cables, a light detector and an irregular transparent surface is provided to detect the presence of liquid in mist and continuous form. The sensor may be integrated into a probe designed for insertion into a pressurized fluid process.

Abstract: The present invention provides electrokinetic microfluidic cytometers useful for detecting and/or sorting fluid-borne particles. In some embodiments, the electrokinetic microfluidic flow cytometer apparatus comprises a substrate having a microchannel formed therein, a particle-sensing gate that reduces the cross-sectional area of a portion of the microchannel, a pair of signal- and noise-detection electrodes, and a particle-detection circuit that is electrically connected to the signal- and noise-detection electrodes and is configured to generate a particle-detection signal responsive to differences in resistivity across the particle-sensing gate.

Abstract: A device (1) is provided for determining at least one parameter of a medium which has a sensor device (2) and an electronic device (3). To provide such a device with a cooling system for at least a portion of its components, the sensor device (2) and/or the electronic device (3) are arranged at least partly in at least one inner space (4, 5) of a housing (6). A passage (7) borders the inner space (4, 5) and a cooling chamber (8) through which a cooling medium can flow is arranged in proximity of the passage (7).

Abstract: A device (1) is provided for determining at least one parameter of a medium which has a sensor device (2) and an electronic device (3). To provide such a device with a cooling system for at least a portion of its components, the sensor device (2) and/or the electronic device (3) are arranged at least partly in at least one inner space (4, 5) of a housing (6). A passage (7) borders the inner space (4, 5) and a cooling chamber (8) through which a cooling medium can flow is arranged in proximity of the passage (7).

Abstract: An automatic optical measurement system (100) is provided. The measurement system (100) includes a sample vial (10) and an automatic optical measurement apparatus (90) configured to receive the sample vial (10). The automatic optical measurement apparatus (90) is configured to detect a presence of the sample vial (10) in the automatic optical measurement apparatus (90) and measure a light intensity of light substantially passing through the sample vial (10) if the sample vial (10) is present. The measured light intensity is related to sample material properties of a sample material within the sample vial (10).

Abstract: A method and device for detecting, differentiating from background and providing partial identification (i.e., classification) for biological particles found in aerosols or surface dust. The method is based on the phenomenon that luminescent excitation-emission (EEM) graphs of microorganisms obtained before and after perturbation by irradiation with ultraviolet light show characteristic patterns which differ according to the type of particle. For example, Bacillus endospores may be distinguished from vegetative bacteria, and gram positive vegetative bacteria may be distinguished from gram negative bacteria, and all these may be distinguished from many types of background particles, e.g. house dust, road dust, and pollen.

Abstract: Provided are a contrast agent for optical imaging, a use thereof and an apparatus using the same. The contrast agent for optical imaging of the present disclosure allows optical imaging without requiring a fluorophore or a luminophore. As a result, the optical images can be acquired without changing the physicochemical properties of a substrate. The contrast agent for optical imaging of the present disclosure may be used as an optical/nuclear bimodal imaging contrast agent for many applications, and allows radiation therapy as well as monitoring of a therapeutic effect thereof through optical imaging at the same time. Further, when a fluorophore is attached thereto, light emission may be enhanced without energy input from outside since light is emitted from the fluorophore, thereby increasing luminescence intensity and improving tissue penetration.

Abstract: A blood counting device comprises a capillary conduit for drawing from a subject in which a radiotracer has previously been injected a quantity of blood in the micro-liter range to produce in the capillary conduit a flow of blood from which beta radiation is emitted. At least one direct beta radiation detector is placed closely adjacent to the capillary conduit. The direct beta radiation detector consists of a semiconductor photodiode which detects the beta radiation from the flow of blood when directly hit by this beta radiation.

Abstract: An example optic module verification device for use in periodic normalization of a testing machine used to test samples in wells is disclosed. The example testing machine includes a plurality of photon counters that each count photons emitted from different wells. The example verification device includes a plurality of verification wells located so as to each be associated with one of the photon counters when used in the testing machine. The example device also includes a photon emitter in each verification well, each photon emitter including a C14 source, a scintillator adjacent the C14 source, and a filter over the scintillator. The example photon emitters each have a determined initial base value for emitted photons, and each photon emitter is positioned in its verification well to emit photons through the filter to the associated photon counter when used in the testing machine.

Abstract: An electrokinetic microfluidic flow cytometer apparatus can include a substrate, a pair of signal and noise detection channels, and a particle detection circuit. The substrate includes an input port, an output port, and a microchannel that fluidly connects the input port and the output port to allow fluid to flow therebetween. The signal and noise detection channels are defined in the substrate and are fluidly connected to the microchannel from locations that are adjacent to each other. The signal and noise detection channels extend in opposite directions away from the microchannel to receive ambient electrical noise. The particle detection circuit generates a particle detection signal in response to a differential voltage across the signal and noise detection channels, which tracks changes in resistivity across an adjacent portion of the microchannel while at least substantially canceling a common component of the ambient electrical noise.

Abstract: In an extreme ultraviolet light source apparatus generating an extreme ultraviolet light from a plasma generated by irradiating a target, which is a droplet D of molten Sn, with a laser light, and controlling the flow direction of ion generated at the generation of the extreme ultraviolet light by a magnetic field or an electric field, an ion collection cylinder 20 is arranged for collecting the ion, and ion collision surfaces Sa and Sb of the ion collection cylinder 20 are provided with or coated with Si, which is a metal whose sputtering rate with respect to the ion is less than one atom/ion.

Abstract: A system to detect a plurality of elements is proposed. The system includes one or more X-ray sources for transmitting X-rays towards a sample and also includes plurality of photon detectors. An array of crystals are arranged in a curvature with appropriate geometry for receiving a plurality of photon energies emitted from the sample and focusing the photon energy on the plurality of detectors. The plurality of photon detectors are spatially arranged at Bragg angles corresponding to signature photon energies to detect the plurality of elements simultaneously.

Abstract: A system to detect a plurality of elements is proposed. The system includes one or more X-ray sources for transmitting X-rays towards a sample and also includes plurality of photon detectors. An array of crystals are arranged in a curvature with appropriate geometry for receiving a plurality of photon energies emitted from the sample and focusing the photon energy on the plurality of detectors. The plurality of photon detectors are spatially arranged at Bragg angles corresponding to signature photon energies to detect the plurality of elements simultaneously.

Abstract: An electrokinetic microfluidic flow cytometer apparatus can include a substrate, a pair of signal and noise detection channels, and a particle detection circuit. The substrate includes an input port, an output port, and a microchannel that fluidly connects the input port and the output port to allow fluid to flow therebetween. The signal and noise detection channels are defined in the substrate and are fluidly connected to the microchannel from locations that are adjacent to each other. The signal and noise detection channels extend in opposite directions away from the microchannel to receive ambient electrical noise.

Abstract: A device for collection of radionuclides includes a mixture of a polymer, a fluorescent organic scintillator and a chemical extractant. A radionuclide detector system includes a collection device comprising a mixture of a polymer, a fluorescent agent and a selective ligand. The system includes at least one photomultiplier tube (PMT). A method of detecting radionuclides includes providing a collector device comprising a mixture comprising a polymer, a fluorescent organic scintillator and a chemical extractant. An aqueous environment is exposed to the device and radionuclides are collected from the environment. Radionuclides can be concentrated within the device.

Abstract: One embodiment of the present invention discloses a film element for detecting authenticity, particularly for security elements, security papers, documents of value, coins, chips, and the like, wherein it includes a transparent film and/or a motif layer or a structured layer, including or representing a luminescent motif. The transparent film is preferably made of polycarbonate or PMMA, and the luminescent motif is preferably introduced into the film element via laser processing, particularly laser engraving, via steel embossing or gravure printing or a kiss-cut method or via perforation.

Abstract: Apparatus derives a sample liquid property and has a container with an outlet section having an overflow edge at a horizontal sample surface. A light source above the surface generates a probe light beam at a non-zero angle ?1 to a normal to the surface. A detector above the surface detects intensity of light emitted out through the surface along a first detection axis forming a non-zero angle ?1 with the surface. An optical barrier between the probe light beam and the first detection axis blocks reflected or scattered light. An inlet section receives sample liquid and has an opening to the main section beneath the sample surface. A separating member separates the sample surface of the inlet section from the sample surface of the main section.

Abstract: The present invention relates to an automatic radioactivity analyzer of mixed liquid beta emitter which comprises: a sample preparation part (1, 2, 3, 4, 5, 6, and 7) for extracting a liquid sample from liquid-phase radioactive nuclear wastes; a sample injection part (9 and 10), including a sample transportation part for transporting a bottled sample to a radioactivity detection part to perform measurement; the radioactivity detection part (11) including two photon multiplier tubes; an exterior gamma-ray source injection part (12) for compensating for measurement efficiency according to quenching effects; a signal processing part (13), including a pre-amplifier circuit (14), a high-voltage generator circuit (15), an analogue-to-digital converter circuit (21), and a digital signal processor (DSP) (24), for generating beta spectrums by the aid of a fast coincidence counter (20) and a multi-channel analyzer (22); a main control PC (25) and a graphic user interface (GUI) program (29) for remotely automatically me

Abstract: The invention relates to an apparatus for preparing a small amount of a radioactive substance combination, including a one-part body, a mixing device integrated in the body and adapted to receive a small amount of chemical substances, and at least one receptacle integrated in the body and connected to the mixing device and adapted to hold a small amount of a chemical substance.

Abstract: An apparatus for detecting particles of interest that are dispersed in a fluid mix, which typically includes other particles. The apparatus typically is associated with an interrogation platform arranged to operate in harmony with an opaque member having an orifice sized to promote single-file travel of the particles there-through. A currently preferred embodiment includes a light pipe configured to impinge stimulation-radiation substantially transverse to a direction of fluid flow through the opaque member. Particles of interest may be tagged using antibody-binding, fluorescing molecules. Stimulation radiation from the source causes the tagged particles to undergo a Stokes-shift emission of fluorescence. The resulting fluorescence is detected by the radiation detector and indicates passage of the particles of interest. One workable opaque member is advantageously included in a thin film assembly carried on a removable and disposable card that is adapted for reception in the interrogation platform.

Abstract: In some embodiments, the present disclosure provides a monitoring device that is capable of autonomously measuring in situ radiation activity in the subsurface, such as tritium activity. In particular embodiments, the device includes a water decomposition reactor which decomposes an aqueous sample, such as a reactor which includes a reactive metal alloy, such as NaK. In further embodiments, the device includes a detector and a hydrogen getter. The hydrogen getter removes hydrogen and tritium gas from the detector, allowing multiple measurements to be made without removal or servicing of the device. The present disclosure also provides instruments having detector and reactor portions separated by an isolation valve. Particular embodiments of the device include a high pressure valve, such as a rotary valve, for selectively placing the device in communication with a sample source, such as liquid in a well.

Abstract: A system (and method) for real-time measurement of trace metal concentration in a chemical mechanical polishing (CMP) slurry, includes an electromagnetic radiation flow cell carrying a CMP slurry, a slurry pickup head coupled to the flow cell, and an analyzer for measuring properties of the slurry flowing through the flow cell.

Abstract: Apparatus and method for measuring the fluorescence of nanodrop liquid samples is described in which the sample is held by surface tension between two anvil surfaces. Each anvil surface has an embedded optical fiber with its end finished flush with the surface in the containment area wetted by the sample with the fiber in line. Sample excitation is provided from the side of the sample remote from the containment area. By selection of the fiber transmission numeric aperture the impact of exciting and ambient light on the measurement is minimized. A method of virtual filtering is taught in which any ambient or exciting light that does impinge on the measuring sensor is corrected by subtracting a scaled representation of the source from the measurement. The method and apparatus is capable of detecting 1 femptomole of sodium fluorescein in 1 microliter of TE buffer.

Abstract: An improved elemental mercury analyzer utilizes a fluorescence assembly in combination with a fluorescence quenching reduction mechanism to detect the concentration of elemental mercury within an emission gas sample, via fluorescence of the mercury within the gas sample, while minimizing fluorescence quenching of the gas sample. In one arrangement, the analyzer contains the emission gas sample under a vacuum or negative pressure while detecting fluorescence of the elemental mercury within the emission gas sample. By performing fluorescence detection of the emission gas sample at reduced pressure relative to the pressure of the as-sampled emission gas, the analyzer reduces the number of particle collisions within the emission gas sample over a certain period of time. Such collisional deactivation, and/or the addition of oxygen depleted gas such as nitrogen to the gas sample, reduces fluorescence quenching of the emission gas sample, improving accuracy of detection of mercury.

Abstract: A wellbore tool for measuring the density of a fluid flowing in a wellbore by a photon attenuation technique includes a tube defining a flow path for the fluid, a photon source at one end of the tube, and a photon detector arranged to receive photons which have passed along the tube. In a preffered implementation, a source which emits coincident photon pairs, preferably 22Na, is used. In this embodiment, the tube defining the fluid flow path has first and second relatively straight and aligned measurement portions disposed on opposite sides of the photon source, so that each measurement portion receives a respective photon of some of the coincident pairs for transmission longitudinally along it. Respective detectors at the other ends of the measurement portions receive respective ones of the photon pairs. The detected coincident photons are counted, and the density of the fluid is derived from the count rate.

Abstract: A pulse discrimination method for discriminating between pulses having a short decay period and a long decay period, may comprise: Detecting the pulse; integrating a rise portion of the pulse; integrating a decay portion of the pulse; and comparing the integrated rise portion of the pulse with the integrated decay portion of the pulse to distinguish between a pulse having a long decay period and a pulse having a short decay period.

Abstract: The present invention relates to the use of nanoscintillation systems, or nanoparticles containing fluor molecules, that can be used to detect an electron-emitting or alpha-particle-emitting radioisotope in the absence of organic-solvents commonly used in organic-based liquid scintillation cocktails. The invention also relates to compositions and use of three oil-in-water microemulsion precursors that can be engineered rapidly, reproducibly, and cost-effectively to produce useful nanoparticles less than 100 nanometers.

Abstract: The present invention relates to the use of nanoscintillation systems, or nanoparticles containing fluor molecules, that can be used to detect an electron-emitting or alpha-particle-emitting radioisotope in the absence of organic-solvents commonly used in organic-based liquid scintillation cocktails. The invention also relates to compositions and use of three oil-in-water microemulsion precursors that can be engineered rapidly, reproducibly, and cost-effectively to produce useful nanoparticles less than 100 nanometers.

Abstract: The invention refers to a device for determining the nuclide content of a radioactive fluid. The device comprises a space (2) for receiving the fluid, a primary detector (6) for detection of gamma radiation emitted form the fluid in the space (2), and a processing member (10) for determining the nuclide content of the fluid based on the detected gamma radiation. The primary detector (6) includes a first detector part (8) having a front end directed towards the space and a second detector part (9) arranged adjacent to said front end between the first detector part (8) and the space (2).

Abstract: A radioactive dust monitor comprising a dust collecting electrode serving also as a radiation detecting surface, an ionization line extending in air in a spaced relation with the dust collecting electrode and a radiation detection part. The radiation detection part is provided with a scintillator disposed close to said dust collecting electrode and a photoelectric conversion part converting light emitted from the scintillator into an electric signal. Dust in air is collected by the dust collecting electrode due to a corona discharge which is generated by applying a negative high voltage to the ionization line and by applying a positive high voltage to the dust collecting electrode, and light emitted from the scintillator due to radioactive rays radiated from the collected radioactive dust is detected by the photoelectric conversion part.

Abstract: The method and apparatus provide a technique for monitoring radioactive source emissions by detecting photons arising from scintillation within the environment of the area or item under monitoring, caused by the passage of emissions from the radioactive source. The technique includes options for excluding ambient light photons through suitable shielding and/or selective in detection of photons from only certain wavelengths or wavebands. The technique enables levels/types and locations of emissions sources to be determined. The technique is applicable to environmental monitoring instruments, scanning instruments and other types.

Abstract: A radioactive dust monitor comprising a dust collecting electrode serving also as a radiation detecting surface, an ionization line extending in air in a spaced relation with the dust collecting electrode and a radiation detection part. The radiation detection part is provided with a scintillator disposed close to said dust collecting electrode and a photoelectric conversion part converting light emitted from the scintillator into an electric signal. Dust in air is collected by the dust collecting electrode due to a corona discharge which is generated by applying a negative high voltage to the ionization line and by applying a positive high voltage to the dust collecting electrode, and light emitted from the scintillator due to radioactive rays radiated from the collected radioactive dust is detected by the photoelectric conversion part.

Abstract: The invention relates to the field of radio-ecological monitoring, in particular to a method for measuring the content of radionuclides in components of the environment. The technical result is enhancement of the sensitivity of liquid scintillation analysis of radionuclides with low activity in the presence of radionuclides with high activity. Selection and preparation of a sample for measurements are carried out, the spectrum of the sample is measured and recorded, the measured spectrum Pi is grouped, model spectrum Mi=&Sgr;cj Mij, wherein cj designates relative contributions of base spectra of radionuclides in the model spectrum, is created on the basis of a library of base spectra of radionuclides Mij, where i is the No.

Abstract: An extraction-scintillation medium of substantially free-flowing, porous, solid particulate matter having one or more fluors retained within the particulate matter and an extraction agent adsorbed on or bound to the surface of the particulate matter. The medium is capable of extracting one of a selected radionuclide from an aqueous stream and permits transmission of light therethrough, which light is emitted from the one or more fluors in response to radiation absorbed thereby from the selected radionuclide. A sensor system using the extraction-scintillation medium for real-time or near real-time detection of the selected radionuclide is also disclosed.

Abstract: A method and apparatus are provided for the position sensitive detection of radioactivity in a fluid stream, particularly in the effluent fluid stream from a gas or liquid chromatographic instrument. The invention represents a significant advance in efficiency and cost reduction compared with current efforts.

Abstract: A method for separation, identification, and quantification of radioactive species in an environmental fluid, such as surface or ground water, by passing the fluid through a sheet article. The sheet article is an essentially homogenous, fibrous or fibrillated, matrix or membrane that includes (1) ion-specific separators that sorb or react with the targeted radioactive species and (2) scintillators which emit light in response to radioactive emissions from the targeted species. The separators can be macrocyclic ligand-containing particles. The scintillators can be particles, fibers, a coating on the particles, or a coating on the fibrous matrix or membrane. The scintillator can be an organic scintillator or an inorganic crystalline scintillator. In one embodiment both the scintillator and the separator are incorporated into the same particle or fiber. A scintillation counter can be used to detect and quantify the emitted light.

Abstract: A method for assay of an analyte by use of a material labeled with a chemiluminescent substance, which comprises adding a quencher and/or decreasing the specific activity of a chemiluminescent substance labeled probe, thereby decreasing the quantity of chemiluminescence.

Abstract: A method and apparatus are provided to concentrate and detect very low levels of radioactive noble gases from the atmosphere. More specifically the invention provides a method and apparatus to concentrate xenon, krypton and radon in an organic fluid and to detect these gases by the radioactive emissions.

Abstract: A continuous sample detector has a cell assembly with a spaced pair of sample cells. Each of these cells is mounted in a sample chamber and each is adapted to conduct a continuous sample flow. These sample cells are connected through a plurality of sample lines. The continuous sample detector also includes a sensor that is mounted and arranged proximate the cell assembly. Relative motion between the sensor and the cell assembly will enable the sensor to alternately detect radiation predominantly from a selected one of the cells. The sensor and the cells are positioned within the common housing to detect radiation with the sensor from predominantly a first one of the sample cells. The sample flow may at that time pass through the first one of the sample cells. The relative position of the sensor and the sample cells may then be changed within the common housing to detect radiation with the sensor from predominantly a second one of the sample cells.

Abstract: A scintillating optical fiber sensitive to low energy radiation has a clear, solid, elongated core with a thin cladding layer surrounding substantially all of the core along substantially all the length of the core and a dye dopant dispersed within the thin cladding layer. When a low energy radiation particle contacts the thin cladding layer, energy from the particle is transferred to photons having a radiant energy frequency determined by the dye dopant color, and a fraction of the photons are transmitted through the fiber by total internal reflection. A detector using the scintillating optical fiber is also disclosed having a sensor for detecting and indicating the presence of photons operatively connected to an end of at least one optical fiber, such that when the fraction of photons are transmitted through the fiber by total internal reflection to the end, the sensor detects the photons and subsequently provides an indication that low energy radiation has been detected.