Abstract: In an embodiment, a method includes receiving a first measurement of gamma rays via a detector during a first period of time, receiving a second measurement of gamma rays via the detector during a second period of time, removing the second measurement from the first measurement to produce an inelastic spectrum, determining a spectral slope from the inelastic spectrum, determining a scaling factor based on the spectral slope, determining a spectral shape associated with the detector, determining a detector-induced spectrum by applying the scaling factor to the spectral shape, and removing the detector-induced spectrum from the inelastic spectrum to produce a clean inelastic spectrum.

Abstract: Methods are provided for determining values for a set of parameters for multiple locations in a formation by inversion of formation data obtained from a plurality of different logging tools. The inversion of the formation data is constrained by certain formation data that characterizes each particular location in the formation as obtained from at least one of the plurality of different logging tools. In one embodiment, the set of parameters for each particular location in the formation includes an apparent cementation factor mn and a formation water saturation Sw, which can be derived by inverting dielectric data that characterizes the particular location in the formation as obtained from a dielectric logging tool. The methods can also be adapted to characterize a porous medium such as reservoir rock, particular with regard to laboratory analysis of porous media samples.

Abstract: An apparatus for sensing acoustic energy in a borehole penetrating the earth includes an optical interrogator and a sensing optical fiber having a length Ls optically coupled to the optical interrogator and configured to sense the acoustic energy to provide sensed acoustic data. The apparatus also includes a reference optical fiber having a length Lr optically coupled to the optical interrogator to provide reference data, wherein the optical interrogator corrects the sensed acoustic data using the reference data to provide corrected sensed acoustic data.

Abstract: In some examples, a computer-readable medium stores executable code which, when executed by a processor, causes the processor to obtain a threshold pulse rate that is based on an average pulse rate of a gamma radiation detector tool and on a desired probability that the threshold pulse rate will not be exceeded by the gamma radiation detector tool. The code also causes the processor to identify instances of pulse from the gamma radiation detector tool that do not exceed the threshold pulse rate, and output an indication of the identified instances of pulses for use in a measurement-while-drilling application.

Abstract: A downhole gamma ray detector having improved resistance to shocks and vibrations encountered during use of modern drilling techniques. The detector includes a scintillator with a window for emitting photons upon receipt of gamma rays. The window faces a photon-receiving end of a photomultiplier tube. The scintillator and the photomultiplier tube are held in a fixed arrangement with respect to each other to provide an empty gap between the window and the photon-receiving end of the photomultiplier tube.

Abstract: System and methods for calibrating gamma ray tools using blanket field calibrator models is provided. A counting rate of a first gamma ray tool is simulated based on a model of a first blanket calibrator. When it is determined that the simulated counting rate matches a measured counting rate associated with the first gamma ray tool, a tally multiplier and a corresponding material specification for the model of the first blanket calibrator is determined. A counting rate for a second gamma ray tool is simulated based on the tally multiplier and the material specification determined for the model of the first blanket calibrator. A sensitivity factor for the second gamma ray tool is determined based on the simulation. The second gamma ray tool is calibrated according to a nominal blanket activity calculated from the sensitivity factor of the second gamma ray tool.

Abstract: Some embodiments of the present disclosure relate to a displacer for reducing the consumption of a cryogen used in a superconductive magnet device. The displacer may occupy some space within the cryogen storage cavity or limit the cryogen into a relatively small space surrounding a superconductive coil in the cryogen storage cavity. The displacer may also include a displacer cavity that may be vacuum or contain a cryogen or another substance.

Abstract: Various apparatus or methods are arranged to operate a tool downhole in a well, where the tool has a detection package operable to detect gamma rays. Deviation of energy spectra of detected gamma rays in each selected energy window of a set of selected energy windows with respect to reference energy spectra of the respective selected energy window can be detected. One or more properties of one or more regions around the tool can be determined from the deviations, the regions being between the tool and a source of the detected gamma rays in a formation around the well. Additional apparatus, systems, and methods having a gamma ray detection package can operate in a variety of applications.

Abstract: A downhole drilling system for reducing effects of overheating comprises a drill string having one or more drill pipes interconnected therebetween, a bottom hole assembly (BHA) connected to a distal end of the drill string, and a controller. The BHA comprises a drill bit disposed at an end portion of the BHA, a downhole motor to rotate the drill bit, a drill collar, in which a centrally disposed passage is formed and drilling mud is supplied to the drill bit through the centrally disposed passage, a measurement instrument disposed in the drill collar to obtain drilling environmental profile and communicating with the controller, and a cooling sub disposed in or on the drill collar or the measurement instrument.

Abstract: Some embodiments of the present disclosure relate to a displacer for reducing the consumption of a cryogen used in a superconductive magnet device. The displacer may occupy some space within the cryogen storage cavity or limit the cryogen into a relatively small space surrounding a superconductive coil in the cryogen storage cavity. The displacer may also include a displacer cavity that may be vacuum or contain a cryogen or another substance.

Abstract: A variety of applications can include a gamma ray downhole logging system having a gamma ray detector, where temperature sensitivity of the gamma ray detector is accounted for in the operation of the logging system. Correction of sensitivity of the gamma ray detector can include using a measure of sensitivity drift derived from temperature binned gamma ray spectra from measurements by the gamma ray detector over a calibration period for a number of calibration periods. Additional apparatus, systems, and methods are disclosed.

Abstract: An apparatus (100) for assessing the condition of the bone tissue in a patient's bone region (21). The apparatus includes an ultrasound device (11) that transmits/receives ultrasounds along a plurality of ultrasound propagation lines (15i) for the bone region (21), and for receiving in response from the bone region (21) a plurality of raw reflected ultrasound signals (36,38); a device for generating an ultrasound signal, a sonographic image formation device for forming a sonographic image (29) of the bone region (21), starting from the raw reflected ultrasound signals (36,38); a device for extracting at least one frequency spectrum (43.sub.i,44.sub.i,47,48) starting from at least one part of said plurality of raw reflected ultrasound signals (36,38) coming from corresponding points (34) of the bone region (21), each having a plurality of harmonic components.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to receive gamma ray measurements from a gamma ray detector; to generate a spectrum based on the gamma ray measurements, the spectrum including a plurality of channels and count rates for the plurality of channels, wherein a channel number of a channel corresponds to energy values of the received gamma rays; to fit a curve to a portion of the spectrum; to determine a location of the maximum of the first derivative of the curve; and to adjust a gain of the gamma ray detector based on the location of the maximum of the first derivative of the curve. Additional apparatus, systems, and methods are disclosed.

Abstract: A system includes a data processing system including a processor operatively coupled to a memory. The processor is configured to receive a first dataset indicative of spectral information regarding photons received from a first detector of a formation density tool. The processor is configured to receive a second dataset indicative of a total count rate of photons from a second detector of the formation density tool. The processor is configured to determine physical characteristics of a geological formation based on the spectral information and the total count rate. The processor is configured to display the physical characteristics of the geological formation in a display.

Abstract: A liquid crystal dropping apparatus and a heating thermos device are provided. The liquid crystal dropping apparatus includes a heating member configured to heat a liquid crystal in the liquid crystal dropping apparatus, a detecting member, configured to detect a temperature of the liquid crystal in the liquid crystal dropping apparatus, and a control unit respectively connected to the heating member and the detecting member. The control unit controls the heating member according to the temperature detected by the detecting member to keep the temperature of the liquid crystal in the liquid crystal dropping apparatus being a predetermined temperature value.

Abstract: A wellbore tool includes a cooling section positioned within the tool for the purpose of maintaining the temperature sensitive components within their rated operating temperature range. The cooling section includes an evaporator, compressor, condenser, power device, expansion device. The compressor is positioned within the condenser. The components whose temperatures are to be maintained are in thermal contact to the evaporator. The cooling process is based upon the vapor compression cycle.

Abstract: Systems, methods, and devices for thermally protecting a scintillator crystal of a scintillation detector are provided. In one example, a thermally-protected scintillator may include a scintillator crystal and a thermal protection element, which may partially surround the scintillator crystal. The thermal protection element may be configured to prevent the scintillator crystal from experiencing a rate of change in temperature sufficient to cause cracking or non-uniform light output, or a combination thereof.

Abstract: A system includes a tool for measuring properties of a formation. The tool includes a tool body, a neutron source to emit neutrons disposed within the tool body, a neutron detector disposed within the tool body spaced apart from the neutron source, and a neutron shield arranged in operational relationship to the neutron detector, the neutron shield defines an exterior surface and an interior volume, the neutron shield to prevent neutrons having an energy below a first predetermined threshold from traveling from the exterior surface to the interior volume. The neutron shield is movably coupled to the tool body, wherein the neutron shield defines a non-occluded position relative to the neutron detector such that the neutron detector is at least partially outside the interior volume, and the neutron shield defines an occluded position relative to the neutron detector such that the neutron detector is disposed within the interior volume.

Abstract: Methods and systems are disclosed wherein neutrons are produced by a photon induced process 2D(?,n) and the ensuing neutrons are thermalized and captured by hydrogen producing a 2.223 MeV gamma that is used to identify and quantify the presence of hydrogen and which, when combined with NRF signals from certain isotopes, can be used to establish the nature of a hydrogenous compound or a mixture of hydrogenous materials or a mixture of hydrogenous materials with other non-hydrogenous materials. The method is useful to establish, e.g., the presence and quantification of explosives, toxic substances and general contraband as well as the flow of materials in a production line or shipping venue.

Abstract: A downhole tool includes a temperature sensitive component. The temperature of the temperature sensitive component is at least partially controlled by a temperature management system thermally coupled to the temperature sensitive component. The temperature management system may include a cold plate thermally coupled to the temperature sensitive component, a hot plate thermally coupled to the cold plate, and a thermo-electrical converter system thermally coupled to the hot plate and to the body of the downhole tool, wherein the thermo-electrical converter system comprises two membrane electrode assemblies.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to receive gamma ray measurements from a gamma ray detector; to generate a spectrum based on the gamma ray measurements, the spectrum including channels and count rates for the channels, wherein a channel number of a channel corresponds to energy values associated with the gamma ray measurements; to generate a ratio of total counts in a first window of the spectrum to total counts in a second window of the spectrum, the first window including a first set of channels starting at a low threshold channel and the second window including a second set of channels; and to adjust a gain of the gamma ray detector responsive to a determination that the ratio is different from a desired ratio. Additional apparatus, systems, and methods are disclosed.

Abstract: Disclosed herein is a system for fast gain regulation in a gamma-ray spectroscopy instrument. The system includes a detector configured to generate a signal indicative of energy arriving at the detector, and a processor configured to determine one or more system performance indicators. The system also includes a controller configured to compute a first gain correction term based on one of more system performance indicators and change the device gain based on the computed first gain correction tem.

Abstract: A radiometric measuring arrangement having at least one radiation source and one detection device for the purpose of detecting radioactive radiation, having a longitudinally extended scintillator for the purpose of generating radiation induced light flashes, a photosensitive element for the purpose of generating an electronic signal based on the light flashes, and an electronic measuring device for the purpose of processing the electronic signals, characterized in that a flexible cooling device is functionally assigned to the scintillator, surrounding the same coaxially, and conveying cooling means.

Abstract: Systems, methods and devices for evaluating an earth formation intersected by a borehole. The method includes using a first radiation responsive component to detect gamma rays having an energy below a threshold energy; using a second radiation responsive component configured to detect gamma rays that traverse the first radiation responsive component; generating a reduced-Compton gamma ray spectrum by generating an anticoincidence gamma ray spectrum indicative of the gamma rays detected by the first radiation responsive component and the gamma rays detected by the second radiation responsive component. The anticoincidence gamma ray spectrum represents those gamma rays of the gamma rays detected by the second radiation responsive component that are not detected in coincidence with the gamma rays detected by the first radiation responsive component.

Abstract: Reducing disturbance during fiber optic sensing. An in-well fiber optic sensing system includes a device insulated to be disturbance-resistant. The device is in a fiber optic communication path between a source and a target configured to be received in a well. The device is configured to receive a parameter sensing signal transmitted from the source to the target and produce a reference signal. The fiber optic sensing system includes a signal interrogation system connected to the device in the fiber optic communication path. The signal interrogation system is configured to receive the reference signal from the device and to receive a response signal from the target in response to the parameter sensing signal. The response signal represents the parameter of interest. The signal interrogation system is configured to determine the parameter of interest based, in part, on the reference signal and the response signal.

Abstract: The present disclosure provides systems and methods where an electron focusing device can be combined with a scintillation detector to better focus the electrons generated by a light sensing device. The scintillation detector can include a scintillation crystal that is covered by an inner light-reflecting coating layer where the scintillation crystal may emit photons due to measurement radiation(s). The light sensing device can include a photomultiplier that may receive the photons emitted by the scintillation crystal and convert them into the electrons generated. The electron focusing device can include a metal ring magnet or one or more conducting coils encircling the scintillation crystal that may create a magnetic field so as to focus the electrons generated by the light sensing device.

Abstract: An improved gamma controller health detection assembly to facilitate reliable downhole measurement of naturally occurring radiation is disclosed. The gamma controller assembly includes one or more gamma sensors, a micro-controller, memory, and input/output ports among other components. The gamma sensors detect radiation and output pulses that are received by the microcontroller. The sensor data can be checked, selected, and averaged by the microcontroller, and sent uphole to another microcontroller or computer that can then further process, communicate, and display the data. The sensor data can be averaged and stored to memory or stored as independent values to memory. The gamma controller health detection assembly can be configured to run algorithms that detect if one or more gamma sensors appear to be malfunctioning or have previously malfunctioned.

Abstract: A radiation detector device is disclosed that includes a scintillator including a scintillator crystal and a hybrid photodetector (HPD) coupled to the scintillator. The HPD includes an electron tube having an input window and a photocathode adapted to emit photoelectrons when light passing through the input window strikes the photocathode. Further, the hybrid photodetector includes an electron detector adapted to receive photoelectrons emitted by the photocathode. The electron detector comprises a semiconductor material characterized by a bandgap of at least 2.15 eV.

Abstract: An improved gamma controller assembly to facilitate reliable downhole measurement of naturally occurring radiation is disclosed. The gamma controller assembly includes multiple gamma sensors, a micro-controller, memory, and input/output ports among other components. The multiple gamma sensors detect radiation and output pulses that are received by the microcontroller. The sensor data can be checked, selected, and averaged by the microcontroller, and sent uphole to another microcontroller or computer that can then further process, communicate, and display the data. The sensor data can be averaged and stored to memory or stored as independent values to memory. The gamma controller assembly can be configured to run algorithms that detect if one gamma controller appears to be malfunctioning and, if an apparent malfunction has occurred, adjust the sensor data that is being sent uphole.

Abstract: Disclosed herein is a system for fast gain regulation in a gamma-ray spectroscopy instrument. The system includes a detector configured to generate a signal indicative of energy arriving at the detector, and a processor configured to determine one or more system performance indicators. The system also includes a controller configured to compute a first gain correction term based on one of more system performance indicators and change the device gain based on the computed first gain correction tem.

Abstract: Systems and methods which provide modeling or simulation of gamma ray (GR) tool response using a hybrid analytical and numerical technique are shown. Embodiments employ a GR tool simulation technique which provides gamma ray information simulated as a function of only the gamma particles which reach the detector without scattering. Embodiments utilize a discretization function to determine the gamma particles which would reach a point detector from each unit volume source of an investigation domain without scattering. Embodiments further utilize the foregoing discretization function with respect to a plurality of point detectors, wherein the particular number and configuration of point detectors are selected to relatively accurately simulate the results of a particular GR detector configuration, such as line detector or volume detector configurations.

Abstract: The present invention relates to a device for transfer of heat energy in a well logging tool, where a variable heat flow from a chamber for electronics via a thermovalve is transmitted into a heat sink consisting of cooled metal, thereby establishing an approximately constant temperature in the chamber for electronics. The device comprises an electronics modular unit and a heat sink modular unit, which modular units are connected via an intermediate section, where a heat-regulating thermovalve provides heat conduction between a conical piston and a conical piston seat, for transferring heat energy.

Abstract: A method is for detecting gamma rays using a gamma ray detector, and includes determining a first count of gamma rays having an energy in a first energy interval, using a controller coupled to the gamma ray detector. A second count of gamma rays having an energy in a second energy interval is determined, the second energy interval having a higher energy than the first energy interval, using the controller. A third count of gamma rays having an energy in a third energy interval is determined, the third energy interval having a higher energy than the second energy interval, using the controller. The second count of gamma rays is compensated for noise based upon a ratio of the second count and the third count, using the controller.

Abstract: A nuclear logging tool calibration system and method. At least some of the illustrative embodiments are methods including placing a logging tool proximate to a volume to be tested (the logging tool comprising a neutron source and a gamma detector), accumulating a spectrum of gammas by the gamma detector (the gammas created responsive to neutron irradiation of the volume by the neutron source), and then adjusting gain of a photomultiplier tube of the gamma detector. The adjusting is responsive to count rate in an overflow bin of the spectrum, where the overflow bin accumulates count rate of gammas received by the gamma detector that have energy above a predetermined energy.

Abstract: A method of forming a scintillator device includes inserting a window into a lumen of a window support ring. The window support ring has an annular structure defining the lumen. The lumen extends between first and second ends of the window support ring. The method also includes inserting a scintillator material into a cavity of a housing defined by an annular sidewall of the housing. The housing has an anterior end and a posterior end. The sidewall defines an opening at the anterior end of the housing. The scintillator material is inserted into the cavity via the opening. The method further includes adhering the window to a front face of the scintillator material and coupling the first end of the window support ring to the annular sidewall of the housing at the anterior end to close the opening.

Abstract: A downhole instrument for estimating density of sub-surface materials includes: a neutron source, a source monitoring detector, a near detector and a far detector. Each of the detectors may be coupled to an electronics unit adapted for receiving a detection signal from each of the detectors and compensating the detection signal for at least one of the near detector and the far detector according to the detection signal of the source monitoring detector. A method for estimating density is provided.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a scintillator material that intrinsically generates radiation and a photodetection system coupled to the scintillator material and adapted to generate electrical signals based on light emitted from the scintillator material. A processing system adapted and programmed to receive the electrical signals, to generate a count rate reference value based at least in part on electrical signals generated in response to the light emitted from the scintillator material due to the intrinsically generated radiation.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a tool body adapted to be deployed in a wellbore and a scintillator material that intrinsically generates radiation. The scintillator material is mounted within the tool body. A photodetection system is coupled to the scintillator material, and mounted within the tool body. Features in a spectrum associated with a scintillation material's intrinsic radioactive decay are used for the determination of one or more parameter's of the response function of the radiation detector system.

Abstract: An instrument for performing measurements downhole includes: at least one gamma-ray detector with azimuthal sensitivity equipped for discriminating energy of incident gamma-rays. This instrument is equipped with or without a neutron or gamma-ray source. A method and computer program product providing the azimuthal sensitivity of the instrument is provided.

Abstract: A system, method and device may be used to monitor conditions in a borehole. Energy is transmitted to a pulse generator located proximate a position to be interrogated with a sensor. The pulse generator stores the energy, then releases it in a pulse of electromagnetic energy, providing the energy to resonant circuits that incorporate the sensors. The resonant circuits modulate the electromagnetic energy and transmit the modulated energy so that it may be received and processed in order to obtain the desired measurements.

Abstract: The present disclosure relates to borehole logging methods and apparatuses for estimating formation properties using nuclear radiation, particularly an apparatus and method for estimating amounts of silicon and/or oxygen in the formation. The method may include using nuclear radiation information from at least one nuclear radiation detector to estimate at least one parameter of interest. The method may include separating a gross nuclear radiation count into separate nuclear radiation components. The method may also include reducing an error in the estimated formation properties due to speed variations of a nuclear radiation source that activates the silicon and oxygen in the formation. The apparatus may include at least one nuclear radiation detector. The apparatuses may include an information processing device to perform the methods.

Abstract: A nuclear logging tool calibration system and method. At least some of the illustrative embodiments are methods including placing a logging tool proximate to a volume to be tested (the logging tool comprising a neutron source and a gamma detector), accumulating a spectrum of gammas by the gamma detector (the gammas created responsive to neutron irradiation of the volume by the neutron source), and then adjusting gain of a photomultiplier tube of the gamma detector. The adjusting is responsive to count rate in an overflow bin of the spectrum, where the overflow bin accumulates count rate of gammas received by the gamma detector that have energy above a predetermined energy.

Abstract: A scintillator device is provided that includes a scintillator device having a scintillator crystal and a shock absorbing member surrounding the scintillator crystal. The scintillator device has a detected light output, ((LO100)/(LO0))×100%, of not less than 88% wherein LO100 is the detected light output of the device after 100 hours of exposure at 175° C. and LO0 is the original detected light output at room temperature prior to exposure at 175° C.

Abstract: An instrument for performing measurements downhole includes: at least one gamma-ray detector with azimuthal sensitivity equipped for discriminating energy of incident gamma-rays. This instrument is equipped with or without a neutron or gamma-ray source. A method and computer program product providing the azimuthal sensitivity of the instrument is provided.

Abstract: A downhole instrument for estimating density of sub-surface materials includes: a neutron source, a source monitoring detector, a near detector and a far detector. Each of the detectors may be coupled to an electronics unit adapted for receiving a detection signal from each of the detectors and compensating the detection signal for at least one of the near detector and the far detector according to the detection signal of the source monitoring detector. A method for estimating density is provided.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a scintillator material that intrinsically generates radiation and a photodetection system coupled to the scintillator material and adapted to generate electrical signals based on light emitted from the scintillator material. A processing system adapted and programmed to receive the electrical signals, to generate a count rate reference value based at least in part on electrical signals generated in response to the light emitted from the scintillator material due to the intrinsically generated radiation.

Abstract: A method for controlling voltage applied to a photomultiplier used in a scintillation counter radiation detector includes determining numbers of voltage pulses having each of a plurality of predetermined amplitudes generated by the photomultiplier in response to radiation events being imparted to a scintillation detector. The numbers of voltage pulses at each of the predetermined amplitudes is conducted to a trained artificial neural network. The artificial neural network generates a signal corresponding to an amount of adjustment to the voltage applied to the photomultiplier.

Abstract: A sintered, annealed scintillator composition, which, prior to annealing, has a formula of A3B2C3O12, where A is at least one member of the group consisting of Tb, Ce, and Lu, or combinations thereof; B is an octahedral site (Al), and C is a tetrahedral site (also Al). One or more substitutions are included. The substitutions may be partial or, in some cases, complete, and can include Al with Sc at B; up to two atoms of oxygen with fluorine and the same number of Ca atoms at A; replacement at B with Mg and the same number of atoms of oxygen with fluorine; replacement at B with a combination of Mg/Si Mg/Zr, Mg/Ti, and/or Mg/Hf; replacement at B with a combination of Li/Nb and/or Li/Ta, and at A with Ca; and replacement of an equal number of B or C with silicon. Related devices are also described, such as CT scanners and well-logging devices.

Abstract: A method for estimating information about a formation, the method including obtaining a first set of radiation data substantially influenced by the formation and non-formation materials; obtaining a second set of radiation data substantially influenced by the non-formation materials; and correcting the first set of radiation data with the second set of radiation data to provide corrected formation radiation data.

Abstract: A gravel pack evaluation tool comprised of a low energy radiation source and multiple directionally-collimated radiation detectors to analyze small, azimuthal segments of a gravel pack. Methods of use are also provided. Collimators and radiation shielding used in conjunction with multiple detector arrays allow an azimuthal segmented view of a gravel pack, particularly at certain defined depths into a gravel pack. Radioactive tracers may be used in conjunction with these tools to produce enhanced images of gravel packs and formations.