87 results about "Neutron emission" patented technology

An apparatus for selective radiation detection includes a neutron detector that facilitates detection of neutron emitters, e.g. plutonium, and the like; a gamma ray detector that facilitates detection of gamma ray sources, e.g., uranium, and the like; and/or an X-ray analyzer that facilitates detection of materials that can shield radioactive sources, e.g., lead, and the like.

The presence of radiation shielding material concealing illegitimate content in a container is detected by obtaining each of measured gamma-ray data and measured neutron data from the container, and comparing the measured gamma-ray and neutron data to expected gamma-ray and neutron data. An anomaly between the measured data and the expected data is an indicum of the presence of such material shielding such illegitimate content.

A neutron imaging apparatus for obtaining an image of the general shape of a neutron emitting source and a bearing of the source relative to the apparatus, the apparatus comprising a chamber comprising a gas with a high probability of interacting with low energy neutrons, releasing collision products that maintain the neutron momentum, and generating ionization particles. The chamber comprises an electrode for providing an electronic signal indicative of the impact location of ionization particles on the electrode and a field to drift the ionization particles to the electrode. A readout indicates the location and time of impact of each ionization particle on the electrode; a memory stores a plurality of the electronic signals; and a computer receives and analyzes the signals and impact times and indicates the location of the source of neutrons by using back projection algorithms to calculate three-dimensional vectors indicative of the neutron path directions.

A nuclear tool includes a tool housing; a d-D neutron generator disposed in the tool housing; a d-T neutron generator disposed in the tool housing; and, optionally, a control circuit for controlling pulsing of the d-D neutron generator and the d-T neutron generator. A method for well-logging using a nuclear tool includes disposing the nuclear tool in a wellbore penetrating a formation; pulsing a d-D neutron generator to emit neutrons at a first energy level into the formation; pulsing a d-T neutron generator to emit neutrons at a second energy level into the formation; and measuring signals returning from the formation.

A portable system for elemental analysis includes one or more neutron emitters, a chamber for containing a test sample, at least one gamma ray detector electrically connected to a data acquisition system, and software or firmware executing on the data acquisition system from a non-transitory physical medium, the software or firmware providing a first function for producing one or more gamma ray spectrums, a second function for applying correction factors to the one or more gamma ray spectrums, and a third function for analyzing the corrected gamma ray spectrum or spectrums to determine a deconvolved elemental composition of the test sample.

A non-radio-isotopic radiological source using a dense plasma focus (DPF) to produce an intense z-pinch plasma from a gas, such as helium, and which accelerates charged particles, such as generated from the gas or injected from an external source, into a target positioned along an acceleration axis and of a type known to emit ionizing radiation when impinged by the type of accelerated charged particles. In a preferred embodiment, helium gas is used to produce a DPF-accelerated He2+ ion beam to a beryllium target, to produce neutron emission having a similar energy spectra as a radio-isotopic AmBe neutron source. Furthermore, multiple DPFs may be stacked to provide staged acceleration of charged particles for enhancing energy, tenability, and control of the source.

The mobile radio unit (phone, smartphone) comprises body 16 with an incorporated processor 1. The processor 1 is connected with memory 2, display 3, audible alarm aids 4, keyboard 5, power unit 6, navigator 9, and transceiver 15. The radio unit is equipped with radiation detector 8, electronic amplifier 7 and interface 10 connected to the processor 1. The detector 8 provides measuring alpha-, beta-, gamma- and neutron emissions and solar radiation levels. The processor 1 is provided with software, which ensures both communication functions and control, warning of exposure levels, measuring background radiation, building diagrams illustrating state of human organs. The keyboard 5 comprises keys for dosimeter and/or radiometer mode control. The detector 8, the interface 10 and the amplifier 7 can be placed in the mobile unit body 16 or in separate detachable unit. Thus, there was constructed an efficient mobile unit, which ensures an extended functionality.

The present invention discloses a system and method for estimating absolute elemental concentrations of a subterranean formation from neutron-induced gamma-ray spectroscopy. In one example, a system (10) for estimating an absolute yield of an element in a subterranean formation may include a downhole tool (12) and data processing circuitry (14). The downhole tool may include a neutron source (18) to emit neutrons into the formation, a neutron monitor (20) to detect a count rate of the emitted neutrons, and a gamma-ray detector (26,28) to obtain gamma-ray spectra deriving at least in part from inelastic gamma- rays produced by inelastic scattering events and neutron capture gamma-rays produced by neutron capture events. The data processing circuitry may be configured to determine a relative elemental yield from the gamma-ray spectra and to determine an absolute elemental yield based at least in part on a normalization of the relative elemental yield to the count rate of the emitted neutrons.

A method for determining at least one formation property calculated from neutron measurements acquired with a downhole tool includes emitting neutrons from a source in the tool into the formation, detecting neutrons with at least one detector in the downhole tool, calculating a first slowing-down length (L₁) based on the detected neutrons, and deriving a second slowing-down length (L₂) based on the first slowing-down length (L₁). Further steps include deriving a correlation function for relating slowing-down lengths from a first tool to slowing-down lengths associated with a different source, wherein the correlation function depends on formation properties such as bulk density; and applying the correlation function to the slowing-down length of the first tool to derive the slowing-down length of the second tool. A method for determining a thermal neutron formation porosity based on a slowing-down length from epithermal neutron measurements from an electronic neutron source includes converting the slowing-down length into a computed neutron slowing-down length from thermal neutron measurements from a chemical neutron source, wherein the converting uses a correlation function that depends on formation bulk density; deriving a thermal neutron countrate ratio based on the computed neutron slowing-down length, wherein the deriving uses a function that depends on the formation bulk density and formation sigma; and computing the thermal neutron formation porosity from the thermal neutron countrate ratio.

In one example, a radiation source comprises a housing and an acceleration chamber within the housing, with a peak acceleration energy greater than the lowest neutron production threshold of tantalum. A source of charged particles is supported by the housing to emit charged particles into the acceleration chamber. A target is supported by the housing downstream of the acceleration chamber. The target consists essentially of at least one isotope having a neutron production threshold greater than the peak acceleration energy. No neutrons are therefore generated. The source may also comprise a collimator, target shielding, and/or housing shielding comprising at least one isotope having a neutron production threshold greater than the peak acceleration energy, reducing or eliminating neutron generation as compared to the prior art, as well. Systems comprising the source, methods of operation of the source, and methods of manufacture of the source are also disclosed.

A method and system for measuring neutron emissions and ionizing radiation, such as gamma emissions, solid state detector for use therein, and imaging system and array of such detectors for use therein are provided using Cd- and/or Hg-containing semiconductors or B-based, Li-based or Gd-based semiconductors. The resulting systems and detectors used therein may be not only compact and portable, but also capable of operating at room temperature. The detectors may also be operable as gamma ray spectrometers.

A neutron emitting assembly, which is useful in nuclear reactors and other industrial applications, is made of a major amount of beryllium encapsulating a minor amount of ²⁵²Cf, which can be placed in a capsule having end plugs and a holding spring.

A method for correcting data collected with a neutron emitting instrument, includes: obtaining characterization data for the instrument, the characterization data including inelastic background data of the instrument; and correcting the collected data according to the characterization data. A computer program product and an instrument are provided.

A movable device for measuring physical quantities of nuclear materials contained in a shielded cell, which device can be brought up against the shielded cell and can be retracted therefrom, the device configured to carry out the measurement in the position in which it is against the shielded cell. The device includes a carriage, a support member placed on the carriage, and a shielded container placed on the support member. The shielded container includes a transfer container configured to store the nuclear material to be measured, and an opening configured to be aligned with an opening in one wall of the shielded cell. The support member is made of graphite and includes a housing accommodating a neutron emission module, a casing covering the shielded container, the casing being made of graphite, and a neutron measurement mechanism fastened to the casing.

Typical practice of the present invention performs measurement and processing of two forms of light emissions—viz., unfiltered and filtered—of a core-valence luminescent (CVL) scintillator impinged by ionizing radiation emanating from a radioactive source. When unfiltered, the CVL scintillator light emission is inclusive of gamma emissions and neutron emissions. When filtered by a filtering apparatus that transmits CVL light only, the CVL scintillator light emission is inclusive of gamma emissions but is exclusive of neutron emissions. Algorithmic comparison between the two sets of empirical data provides discriminative information regarding gamma emissions versus neutron emissions. Essentially, the difference is taken between the unfiltered pulse height spectra data and the filtered pulse height data. The set of pulse height spectral data thus computed via subtraction is indicative of the portion of the CVL scintillator light emissions that is inclusive of neutron emissions but is exclusive of gamma emissions.

The invention discloses a multi-source spacing measurement device and method for neutron porosity during drilling. The measurement device includes a non-magnetic drill collar, a neutron emission unit,a fast neutron monitoring unit, a hot neutron detecting unit and a control unit; the neutron emission unit contains multiple accelerator neutron sources, the fast neutron monitoring unit includes multiple fast neutron monitor groups, the hot neutron detecting unit includes multiple hot neutron detector groups, and the control unit is connected to the neutron emission unit, the fast neutron monitoring unit and the hot neutron detecting unit separately. The multi-source spacing measurement device and method for the neutron porosity during drilling overcome the defects in the prior art, ensure the flexibility and data accuracy of detecting instruments under a complex geologic condition, effectively reduce the influences of well hole parameters, vibration, impact and random fluctuation of measurement data on the measurement result, solve problems in prior art, remove limitations in the prior art, and achieve accurate acquirement of stratum porosity parameters.