Abstract: The radiation detector includes tissue equivalent bubbles of plastic defining volumes of gas to be ionized by radiation. One or more integrated circuits (ICs) are disposed below the volumes of gas and a collecting electrode on the IC is in direct contact with the gas. Circuitry for generating an electric field within the volume of gas moves the ions therein to the collecting electrode. The collecting electrode is part of an amplifying circuit disposed within the IC. The output from the amplifier is representative of the collected ions and therefore representative of the radiation. The signal from the amplifier is send to an interface which conditions, buffers and stores the signal. The radiation dose and dose rate are computed in the interface. A communications section transfers that data from the radiation detector. A separate calibration and display unit calibrates the interface by controlling The conditioning of the signal. An area monitor and air monitor are further enhancements of the radiation detector.

Abstract: A kinestatic charge detector, which detects propagating energy includes a gas ionization chamber with an angled window, between top and bottom surfaces of the chamber, for receiving the propagating energy therethrough. A medium is contained within the chamber for interacting with the incident energy to produce secondary energy. The chamber also includes a device for changing the position of the secondary energy relative to the medium and a detecting device for detecting the secondary energy in the chamber.

Abstract: A dosimeter that includes tissue equivalent bubbles of plastic defining volumes of gas to be ionized by radiation. One or more integrated circuits (ICs) are disposed below the volumes of gas and a collecting electrode on the IC is in direct contact with the gas. Circuitry for generating an electric field within the volume of gas moves the ions therein to the collecting electrode. The collecting electrode is part of an amplifying circuit disposed within the IC. The output from the amplifier is representative of the collected ions and therefore representative of the radiation. The signal from the amplifier is sent to an interface which conditions, buffers and stores the signal. The radiation dose and dose rate are computed in the interface. A communications section transfers that data from the dosimeter upon receipt of an externally generated data transfer command. A separate calibration and display unit calibrates the dosimeter by controlling the conditioning of the signal.

Abstract: A technique for detecting the spatial distribution of propagating energy induces secondary energy produced in a detector to drift in a predetermined direction at a predetermined velocity and synchronously moves the detector in a direction opposite to the direction of drift of the secondary energy at a velocity equal in magnitude to the magnitude of the velocity of drift of the secondary energy. Although the secondary energy is drifting with respect to the detector, the synchronous detector movement causes the secondary energy to appear stationary with respect to a source of radiation, resulting in "kinestatis" of the secondary energy. The secondary energy resulting from the radiation integrates along stationary paths in the detector (operated as a "kinestatic detector") and is subsequently detected when a collection volume of the detector sweeps through the stationary secondary energy.

Abstract: Pulse pile-up rejection in nuclear and X-ray spectrometry is reduced or eliminated by providing the low-pass filter with a storage element which is charged to the value substantially by the voltage step generated by a quantum of radiation before the filtering process commences and only then effecting the filtering process. The step values before and after the rise of the step can be detected and with storage of the previous value, the energy proportional output can then be detected as the difference. The method and apparatus eliminates the rise time of the storage element as a factor contributing to pulse pile-up.

Abstract: A parallel plate counter utilizes avalanche event counting over a large area with the ability to locate radioactive sources in two dimensions. One novel embodiment comprises a gas-filled chamber formed by a stretched stainless steel window cathode spaced from a flat semiconductive anode surface between which a high voltage is applied. When a beta ray, for example, enters the chamber, an ionization event occurs and the avalanche effect multiplies the event and results in charge collection on the anode surface for a limited period of time before the charge leaks away. An encoder system, comprising a symmetrical array of planar conductive surfaces separated from the anode by a dielectric material, couples charge currents the amplitude of which define the relative position of the ionization event. A number of preferred encoder system embodiments are disclosed including a novel matrix or grid pattern of electrical paths connected to voltage dividers and charge sensitive integrating amplifiers.

Abstract: A system for mapping radioactive specimens comprises an avalanche counter, an encoder, pre-amplifier circuits, sample and hold circuits and a programmed computer. The parallel plate counter utilizes avalanche event counting over a large area with the ability to locate radioactive sources in two dimensions. When a beta ray, for example, enters a chamber, an ionization event occurs and the avalanche effect multiplies the event and results in charge collection on the anode surface for a limited period of time before the charge leaks away. The encoder comprises a symmetrical array of planar conductive surfaces separated from the anode by a dielectric material. The encoder couples charge currents, the amplitudes of which define the relative position of the ionization event. The amplitude of coupled current, delivered to pre-amplifiers, defines the location of the event.

Abstract: The specification describes a case for use with a hand-portable chemical agent detector for continuously monitoring an atmosphere for the presence of predetermined chemical agents. The detector having means for ionizing air samples and providing at an output terminal electrical signals representative of the mobility spectrum of ionized chemical vapors produced by the ionizing means. The case comprises means defining a chamber in the case for supporting and removably enclosing the detector, means for communicating ambient atmosphere to the chamber, electrical circuit means in the case, the circuit means being adapted to be detachably connected to the detector output terminal when the detector is positioned in the chamber and being responsive to the electrical signals for producing an alarm signal when the signals detect a chemical agent concentration in the atmosphere exceeding a predetermined concentration level, and alarm means responsive to the alarm signal.

Abstract: A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods.

Abstract: Novel large area spark chamber having a support for carrying a generally planar, radioactive work piece. The spark chamber has a thin window which is either a rigid plastic sheet carrying a thin layer of an electrically conductive material on the surface thereof, or a thin planar piece or film of electrically conductive metal. There is positioned in superposed relationship to the thin window, a layer of semi-conducting glass in spaced-apart relationship from the thin window by a resilient insulating seal to form an enclosed gas retaining chamber. An electrically conducting surface is adhered to the upper surface of the layer of semi-conducting glass. An electrically conductive path is provided between the thin layer of electrically conductive material on the thin window and the electrically conducting surface on said semi-conducting glass. The electrically conductive path includes a high voltage supply and TDCs and ADCs.

Abstract: The invention relates to apparatus for detecting a constituent gas in a gas flow. Means is provided for removing the constituent gas from a sample flow and directing this sample flow together with a reference flow containing the constituent gas through an equilibrator means wherein contaminants can be removed before the sample gas and the reference gas are compared in detector means, for example, an electron capture detector. The apparatus and method are also applicable to the detection of a liquid in a flow thereof.

Abstract: A battery powered device which can continuously monitor and detect nuclear radiation utilizing fully integrated circuitry and which is provided with an alarm which alerts persons when the radiation level exceeds a predetermined threshold.

Abstract: A spark chamber frame 8 is manufactured using only inorganic materials. Spark chamber frame 8 includes a plurality of beams 10, 12, 14, and 16 formed from inorganic material, such as ceramic or glass, and are connected together at ends 9 with inorganic bonding material having substantially the same thermal expansion as the beam material. A plurality of wires 18 and 20 formed from an inorganic composition are positioned between opposed beams 10 and 14 and 12 and 16 so that wires 18 and 20 are uniformly spaced and form a grid. A plurality of hold-down straps 22, 23, 24, and 25 are formed of inorganic material such as ceramic or glass having substantially the same chemical and thermal properties as the beam material. Hold-down straps 22, 23, 24, and 25 overlie wires 18 and 20 extending over beams 10, 12, 14, and 16 and are bonded thereto with inorganic bonding material.

Abstract: A method of stabilizing operation of a hybrid spark chamber is disclosed. The method is applied to a self-triggering hybrid spark chamber of the gas-flow type including a spark chamber portion and a proportional chamber portion, and utilizes a high speed discharge circuit for the proportional chamber portion, the high speed discharge circuit being so constructed that upon generation of a precedent spark in the spark chamber portion by electrons produced by radiation and multipled in the proportional chamber portion the discharge circuit is simultaneously operated in response to the spark so as to rapidly lower an electric field intensity of the proportional chamber portion, thereby preventing the generation in the proportional chamber of any induced spark.

Abstract: An electron capture detector in which a thermionic source such as a filament provides electrons for the reaction in a source chamber having a port that connects to a detection chamber having a collector. Guard gas is introduced into the source chamber and sample gas into the detection chamber, and an exhaust port is provided in the detection chamber.

Abstract: A radiation detector array and a method for measuring the spectral content of radiation. The radiation sensor or detector is an array or stack of thin solid-electrolyte batteries. The batteries, arranged in a stack, may be composed of independent battery cells or may be arranged so that adjacent cells share a common terminal surface. This common surface is possible since the polarity of the batteries with respect to an adjacent battery is unrestricted, allowing a reduction in component parts of the assembly and reducing the overall stack length. Additionally, a test jig or chamber for allowing rapid measurement of the voltage across each battery is disclosed. A multichannel recorder and display may be used to indicate the voltage gradient change across the cells, or a small computer may be used for rapidly converting these voltage readings to a graph of radiation intensity versus wavelength or energy.

Abstract: An electron capture detector in which electrons for the reaction are supplied by a filament in a cylinder through which guard gas is passed. Apertures in the cylinder permit electrons from the filament to pass into an annular space surrounding the cylinder and between it and a collector. Sample gas is passed between the aperture and the collector, the pressures being such as to be capable of minimizing the diffusion of sample gas to the filament.

Abstract: The device is able to detect the exceeding of a given threshold by a parameter, other than an electric voltage, capable of affecting the electrostatic force of attraction exerted between a charged electret and one, of two electrodes between which said electret is placed, said parameter being for instance an ionizing radiation. The two electrodes are at the same electric potential and the device also comprises return means for urging the first electrode and the electret permanently apart, and means for using the relative displacement of said elements, when it occurs, for desired detection purposes.

Abstract: A normally nonconducting liquid such as liquid hydrocarbon is encased between a pair of electrodes in an enclosure so that when the liquid is subjected to ionizing radiation, the ion pairs so created measurably increase the conductivity of the fluid. The reduced impedance between the electrodes is detectable with a sensitive ohm-meter and indicates the amount of ionizing radiation. The enclosure, the electrodes and the fluid can be constructed of materials that make the response of the detector suitable for calibrating a large range of radiation energy levels. The detector is especially useful in medical applications where tissue equivalent X ray detectors are desired.

Abstract: An improved ionization chamber type x-ray detector comprises a heavy gas at high pressure disposed between an anode and a cathode. An open grid structure is disposed adjacent the anode and is maintained at a voltage intermediate between the cathode and anode potentials. The electric field which is produced by positive ions drifting toward the cathode is thus shielded from the anode. Current measuring circuits connected to the anode are, therefore, responsive only to electron current flow within the chamber and the recovery time of the chamber is shortened.The grid structure also serves to shield the anode from electrical currents which might otherwise be induced by mechanical vibrations in the ionization chamber structure.

Abstract: An ionization chamber for use in determining the spatial distribution of x-ray photons in tomography systems comprises a plurality of substantially parallel, planar anodes separated by parallel, planar cathodes and enclosed in a gas of high atomic weight at a pressure from approximately 10 atmospheres to approximately 50 atmospheres. The cathode and anode structures comprise metals which are substantially opaque to x-ray radiation and thereby tend to reduce the resolution limiting effects of x-ray fluoresence in the gas.In another embodiment of the invention the anodes comprise parallel conductive bars disposed between two planar cathodes.Guard rings eliminate surface leakage currents between adjacent electrodes.

Abstract: An improved early warning fire detector of the ionization type is provided wherein detection circuitry having adjustable sensitivity is connected to an ionization chamber responsive to products of combustion. A supervisory circuit monitors the unit to assure that power is applied to the unit, that the detecting circuitry is operative and that the unit is operating at the proper sensitivity.

Abstract: A device for localizing neutrons is made up of modular elements placed within an enclosure which is transparent to neutrons and filled with a gas, each modular element being constituted by a series of parallel wire anodes, means for producing an electric field around each anode wire so as to give rise to charge multiplication when an electron penetrates into the field, a cathode placed in the proximity of the array of wire anodes, means for attaching the anode wires to the cathode walls and means for providing electrical insulation between the cathode and each anode wire.

Abstract: Ion chambers adapted for use with radiant energy in the vacuum ultraviolet and X-ray spectral regions are provided wherein the ion repeller and collector electrodes are configured to provide an electric field therebetween which has a non-uniform potential gradient allowing a photon beam to be passed through a region of low field strength. A further aspect of the configuration of the ion repeller and collector electrodes is the elimination of the need for guard rings.

Abstract: A monitoring device transparent to ionizing radiation, designed to measure the orientation, intensity and uniformity of an incident beam, comprises a cylindrical housing forming at least one ionization chamber with one or more ion-collecting electrodes transverse to the housing axis, each electrode being subdivided into a plurality of mutually insulated conductive elements connected to respective amplifiers. The elements of at least one electrode include one or more outer elements surrounding or bracketing one or more inner elements to measure the radiation in a central zone and a peripheral zone. The outputs of the respective amplifiers are additively and subtractively combined in an evaluation circuit.

Abstract: A smoke detector is disclosed which comprises an inner electrode, an intermediate electrode with a hole for passing radioactive rays therethrough, an outer electrode having openings for allowing smoke to flow therethrough, and one radioactive source, the inner and intermediate electrodes forming an inner ionization chamber, the intermediate and outer electrodes forming an outer ionization chamber, the radioactive source being disposed in the inner ionization chamber. A proper quantity of radioactive rays from the radioactive source is applied into the outer ionization chamber through the hole provided in the intermediate electrode.

Abstract: An ionization smoke detector particularly suited to residential use is disclosed. The detector is battery-operated and is connected with a non-latching, pulsating alarm circuit. The detector has a sensing chamber formed by a perforated metallic shell and an electrode within which an insulated radiation source is centrally positioned to generate an ionization current for detecting smoke or other similar aerosols. The alarm circuit provides a pulsating alarm signal when smoke levels above a predetermined value are sensed. The alarm circuit also includes a low voltage detection circuit for sounding the alarm when the end of useful battery life is approaching.