Abstract: A radiation detection method and system for continuously correcting the quantization of detected charge during pulse pile-up conditions. Charge pulses from a radiation detector responsive to the energy of detected radiation events are converted to voltage pulses of predetermined shape whose peak amplitudes are proportional to the quantity of charge of each corresponding detected event by means of a charge-sensitive preamplifier. These peak amplitudes are sampled and stored sequentially in accordance with their respective times of occurrence. Based on the stored peak amplitudes and times of occurrence, a correction factor is generated which represents the fraction of a previous pulses influence on a preceding pulse peak amplitude. This correction factor is subtracted from the following pulse amplitude in a summing amplifier whose output then represents the corrected charge quantity measurement.

Abstract: In fire detector apparatus for monitoring an extended area from an elevated location, and especially for detecting forest fires, a scanning assembly (1) has azimuthal freedom of movement. A row of adjoining infrared detector element pairs (S, S') is disposed on a common support (7) in the focal plane of a reflector (6). Detector extent or area increases from the optical axis upward, and the detectors are connected with decreasingly sensitive circuitry. As a result, detection areas having different elevations have nearly equal distance range, and detection sensitivity is essentially independent of distance so that a remote forest fire is detected with the same degree of certainty as one close by. For the elimination of false alarms due to diffuse thermal radiation, detector elements are arranged in pairs, side-by-side on the same support (7), and connected in differential circuitry.

Abstract: Art objects are authenticated by using a pair of sealed radioactive sources emitting identical gamma ray spectra unique to that pair. One of the sources is attached to a particular, assigned art object. The surface of the other source is engraved with information relevant to the identity of the particular art object. At a late date, the gamma ray spectra of both sources are obtained and compared, and if they are identical, the art object is authenticated.

Abstract: A personal electromagnetic radiation monitor includes an electromagnetic radiation sensor, a conductive shield spaced apart from the sensor and a backing of graduated lossy material. The electromagnetic radiation sensor includes thin film resistive thermocouples. The backing of graduated lossy material is interposed between the radiation sensor and the conductive shield. The layer is progressively more conductive through its thickness from the side which faces the sensor to the side which faces the conductive shield.

Abstract: A passive infrared radiation (PIR) detection system permits data developed by the PIR detection system to be interpreted, to in essence "look into" a protected area and to positively determine the character of any images detected in the protected area. The system includes an array of PIR detectors for monitoring defined zones of the region to be protected. The array of PIR detectors is contained within an enclosure which is further provided with a lensing system which permits the several PIR detectors to monitor respectively assigned zones of the protected region from a single vantage point. The array of PIR detectors operates to develop a series of electrical signals which are then passed on for further processing and interpretation in accordance with various prescribed tests (criteria) which operate to distinguish between an intruder and other legitimate images capable of exciting the PIR detection system.

Abstract: In a passive infrared intrusion detection system, a signal responsive to infrared radiation received from optically divided zones of an area to be monitored is integrated to produce an integral sum. The integral sum is used to generate an alarm indication. The alarm indication is thereby responsive to the energy of the signal responsive to the infrared radiation received, thus improving sensitivity of the detection system without increasing susceptibility of generating a false alarm.

Abstract: A method of and apparatus for measuring radioactivity, which determines energy spectra of radiation rays which are detected by a radiation sensor through a collimator arranged in front of a radiation detector, calculates a spectrum index on the basis of an intensity of scattered rays and an intensity of unscattered rays among the radiation rays determined by distribution of the energy spectra, calculates a density of the object to be measured or a value relating to the density of the density of the object to be measured on the basis of the spectrum index, and meters the radioactivity of the object to be measured on the basis of the value relating to the density and the intensity of the unscattered rays by one measuring step for every cross-section of the object to be measured.

Abstract: The intrusion detection system of the invention, in which three pyroelectric detectors are disposed in line with a interval and an adjoining two of the three pyroelectric detectors are electrically connected to cancel electrical charges generated by each pyroelectric detector, detects intrusion of an infrared ray radiating object such as a human body for example by output signals outputted from the adjoining two and the other of the three pyroelectric detectors or by output signals outputted from the pyroelectric detector disposed at the center and adjoining one and output signals outputted from the one disposed at the center and adjoining another one of these pyroelectric detectors, so that precise and secure intrusion detection is possible by reducing erroneous signals generated by those pyroelectric detectors due to variation of the atmospheric temperature and the like.

Abstract: A thin, flexible, hollow fiber capable of transmitting ionizing radiation. Ionizing radiation enters the fiber through entrance pupil (10) and travels through the hollow interior of fiber body (20) by reflecting and scattering off the inner wall of the fiber, frequently at grazing incidence angles. Fiber body (20) is covered at one end by thin film cap (30) which is thin enough to be at least semitransparent to ionizing radiation, but which is also strong enough to allow air to be withdrawn from fiber body (20) at the opposite uncapped end. Small obstructions (32) at the exit end of the fiber can be used to spread the beam of ionizing radiation to a desirable width. A flexible fiber capable of transmitting ionizing radiation has important applications in medicine for the radiation therapy of tumors. Applications also exist in communications and other fields.

Abstract: A .gamma. ray emitted from a reference radioactive ray source is radiated from outside to a solid radioactive waste. The radioactive intensity of the .gamma. ray emitted from the solid radioactive waste is measured during the radiation of the .gamma. ray. The radioactive intensity to be measured is discriminated into the first radiation intensity based on the reference radioactive ray source and the second radiation intensity based on the radioactive nuclide of the solid radioactive waste. A radiation absorption coefficient of the solid radioactive waste is determined based on the first radiation intensity. The distribution of radioactivity of the solid radioactive waste is determined based on the radiation absorption coefficient and the second radiation intensity.

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 sample 10 of a composite material, such as a graphite-epoxy composite, is exposed to radiation in three distinct energy bands emanating from sources 12, 13 and 14, respectively. Corresponding detectors 16, 17 and 18 are positioned to measure the amount of energy in each band transmitted through the sample. Weight percentages of three different constituents of the sample 10 are calculated from a relatively simple algorithm whose variables include a ratio for each of said energy bands of the amount of energy that would be detected if the sample were not present in the radiation to the amount of energy transmitted through the sample when the sample is exposed to the radiation.

Abstract: In a radiographic method, first and second collimator elements are arranged between a radiation source and an image converter. When an object is irradiated with radiation beams, the collimatar elements can be switched between first and second states. In the first state, the collimator elements pass both some of the transmitted radiation beams which are not scattered by the object and transmitted therethrough and scattered radiation beams which are scattered by the object so that a first radiation image is obtained in the form of electrical signals based on the transmitted radiation beams and the scattered radiation beams. In the second state, the collimator elements pass only some of the scattered radiation beams scattered by the object so that a second radiation image is obtained in the form of electrical signals based on only the scattered radiation beams.

Abstract: A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

Abstract: A method of and apparatus for sorting pieces or particles of radioactive ore where the particles are moved one after another substantially horizontally then discharged into a gravity-accelerated trajectory which is substantially free-fall but can be controlled to follow a modified path by a low-friction slide plate. The falling particles pass a plurality of radiation detectors arranged in line along their path with increasing velocity due to gravity providing the required separation of the pieces so that each detector is subject to the radiations of essentially only one piece at a time. The size and number of detectors and the path length covered by the detectors is determined by the size of the pieces and the cut-off grade and accuracy required. All counts corresponding to a particular piece and derived successively from the plurality of detectors are accumulated since accuracy increases and percentage of probable error decreases with increased total count.

Abstract: The invention relates to a method of detecting electromagnetic or corpuscular radiation. In order to detect a radiation photon or particle, a homogenous particle of superconducting material of the first form is made to change from the metastable form of the superconducting state to the normal state by the action of a photo-electron expelled by the impact of the photon or particle of radiation on the particle of material.

Abstract: An improved method, and apparatus for said method, for providing protection for an operator during the determination of radioactivity, and most especially during the assay of relative concentrations of two radioactive materials in a radioactive solution, are provided. The process for determining the relative concentrations, by comparing the total radiation emitted by a solution in a substantially unshielded vessel with the breakthrough radiation emitted by a shielded vessel of the solution, is improved by utilizing a special shielding container for the radioactive solution which can be used to provide the necessary shielding, for the breakthrough test, and can be removed, for measuring total radiation, without removing the solution from the radiation measuring means, thus avoiding direct human exposure to radiation, and which is also suitable for subsequent use as a protective container for the radioactive solution during medical diagnostic or other utilization following assay.

Abstract: A dosimetry technique for high-energy gamma radiation or X-radiation employs the Compton effect in conjunction with radiation-induced thermally activated depolarization phenomena. A dielectric material is disposed between two electrodes which are electrically short circuited to produce a dosimeter which is then exposed to the gamma or X radiation. The gamma or X-radiation impinging on the dosimeter interacts with the dielectric material directly or with the metal composing the electrode to produce Compton electrons which are emitted preferentially in the direction in which the radiation was traveling. A portion of these electrons becomes trapped in the dielectric material, consequently inducing a stable electrical polarization in the dielectric material.

Abstract: This invention provides a method of measuring exposure to radiation, particularly x-rays, gamma rays and other forms of penetrating radiation. A dielectric body is provided and is equipped with a pair of electrodes on opposite sides thereof. In accordance with one procedure which may be called radiation induced thermally activated depolarization (RITAD), an electrostatic bias polarization is produced in the dielectric body, preferably by heating it to an elevated temperature, impressing a voltage between the electrodes to produce internal polarization in the body, and cooling the body while maintaining the voltage, so as to freeze in the bias polarization. The voltage is then removed, and the electrodes may be short circuited. The body is then exposed to the radiation to be measured. After such exposure, a current measuring circuit is established between the electrodes. The electrical currents in such circuit are observed and measured as the energy level of the body is raised, preferably by heating the body.

Abstract: A parallel-plate variable-gap diode is described which is used to detect X nd gamma radiation pulses. The collector of the diode is comprised of an interior circular portion and a concentric external annular portion, the collecting surfaces of which are coplanar and noncontiguous. A shielded low-inductance resistor-ring shunts the bulk of the sampled current back through the annular portion of the collector to the emitter thereby reducing self-bias effects. The central location and relatively small size of the current sampler minimize the perturbing influence of the walls at the periphery of the cavity. A one-dimensional electron transport analysis can therefore provide the link between the incident radiation and the observed current response of the diode. The cylindrical walls of the cavity are interchangeable spacers which permit the variation of separation between emitter and collector.

Abstract: Method of determining the distance between an area under fire and the muzzle of the weapon by means of autoradiography of the irradiated firing residues on this area. Several carrier areas are fired at from various distances. The carrier areas are subsequently activated by neutron irradiation and subsequently contacted with a film sensitive to nuclear radiation. The series of autoradiographs produced after development on the film are compared with the autoradiograph, produced in the same way, of the firing trace to be investigated on the area fired at and used as a distance standard for that trace.