Lawrence Livermore National Laboratory

Thermal Cycler
William J. Benett, John T. Andreski, John M. Dzenitis, Anthony J. Makarewicz, Dean R. Hadley, Satinderpall S. Pannu
U.S. Patent 8,778,663 B2
July 15, 2014
A thermal cycler includes two thermal cycler body sections, each with a face. A cavity is formed by the first and second faces, inside of which a thermal cycling unit is positioned. A heater trace unit is connected to a support section, the two thermal cycler body sections, and the thermal cycling unit. The two sections are positioned together against the support section to enclose both the thermal cycling unit and the heater trace unit.

Plasmon Resonant Cavities in Vertical Nanowire Arrays
Mihail Bora, Tiziana C. Bond, Benjamin J. Fasenfest,
Elaine M. Behymer
U.S. Patent 8,780,439 B2
July 15, 2014 Tunable plasmon resonant cavity arrays in paired parallel nanowire waveguides are presented. Resonances can be observed when the waveguide length is an odd multiple of quarter plasmon wavelengths, consistent with boundary conditions of node and antinode at the ends. Two nanowire waveguides can satisfy the dispersion relation of a planar metal–dielectric–metal waveguide whose equivalent width is equal to the square-field average-weighted gap. Confinement factors of over 103 are possible due to plasmon focusing in the interwire space.

Nanoscale Array Structures Suitable for Surface Enhanced Raman Scattering and Methods Related Thereto
Tiziana C. Bond, Robin Miles, James C. Davidson, Gang Logan Liu
U.S. Patent 8,786,852 B2
July 22, 2014
These methods are used to fabricate and characterize nanoscale array structures for surface-enhanced Raman scattering. Nanoscale array structures may comprise nanotrees, nanorecesses, and tapered nanopillars.

Electron Beam Diagnostic System Using Computed Tomography and an Annular Sensor
John W. Elmer, Alan T. Teruya
U.S. Patent 8,791,426 B2
July 29, 2014
A system for analyzing an electron beam includes a circular electron-beam diagnostic sensor adapted to receive the electron beam. The sensor has a central axis, and connected to the sensor is an annular sensor structure that receives the electron beam. The system sweeps the electron beam radially outward from the central axis of the electron-beam diagnostic sensor to the annular sensor structure, wherein the beam is intercepted and measured.

Optical Waveguides Having Flattened High Order Modes
Michael Joseph Messerly, Raymond John Beach, John Edward Heebner, Jay Walter Dawson, Paul Henry Pax
U.S. Patent 8,798,422 B2
August 5, 2014
A deterministic methodology is provided for designing optical fibers that support field-flattened, ringlike higher order modes. The effective and group indices of these modes can be tuned by adjusting the widths of the guide’s field-flattened layers or the average index of certain groups of layers. The approach outlined here provides a path to designing fibers that simultaneously have large mode areas and large separations between the propagation constants of the modes.

Harmonic Engine
Charles L. Bennett, Noel Sewall, Carl Boroa
U.S. Patent 8,807,012 B1
August 19, 2014
This engine is based on a reciprocating piston engine that extracts work from pressurized working fluid. The engine includes a harmonic oscillator inlet valve capable of oscillating at a resonant frequency for controlling the flow of working fluid into the engine. In particular, the inlet valve includes a valve head and a spring arranged together as a harmonic oscillator so that the inlet valve head is movable from an unbiased, equilibrium position to a biased, closed position to occlude the inlet. When the inlet valve is released, the inlet valve head undergoes a single oscillation past the equilibrium position to a maximum, open position and returns to a biased, return position near the closed position. In this way, it chokes the flow and produces a pressure drop across the inlet valve, causing the valve to close. Protrusions carried by either the inlet valve head or the piston head are used to bump open the inlet valve from the closed position and initiate the single oscillation of the inlet valve head. Protrusions carried by either the outlet valve head or the piston head are used to close the outlet valve ahead of the bump that opens the inlet valve.

Carbon Ion Pump for Removal of Carbon Dioxide from Combustion Gas and Other Gas Mixtures
Roger D. Aines, William L. Bourcier
U.S. Patent 8,808,433 B2
August 19, 2014
This ion pump system is designed to separate carbon dioxide from flue gas. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method dramatically increases the concentration of dissolved carbonate ion in solution. The overlying vapor pressure of carbon dioxide gas is thus increased, permitting carbon dioxide as a pure gas to be removed from the downstream side of the ion pump. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination, or an ion pump system that has an oscillating flow synchronized with an induced electric field.

Fluidics Platform and Method for Sample Preparation and Analysis
W. Henry Benner, John M. Dzenitis, William J. Benett, Brian R. Baker
U.S. Patent 8,808,643 B1
August 19, 2014
Herein provided are a fluidics platform and a method for sample preparation and analysis. The fluidics platform can analyze DNA from blood samples using amplification assays such as polymerase chain reaction and loop-mediated isothermal amplification. The platform can also be used for other types of assays and analyses. In some configurations, a sample in a sealed tube can be inserted directly. The following isolation, detection, and analyses can be performed without a user’s intervention. The disclosed platform may also comprise a sample preparation system with a magnetic actuator, a heater, and an air-drying mechanism. Fluid manipulation processes include extraction, washing, elution, assay detection, and cleaning after reactions and between samples.

Porous Substrates Filled with Nanomaterials
Marcus A. Worsley, Theodore F. Baumann, Joe H. Satcher, Jr., Michael Stadermann
U.S. Patent 8,809,230 B2
August 19, 2014
This composition has at least one carbon monolith, such as a carbon aerogel, with internal pores and at least one nanomaterial, such as carbon nanotubes, disposed uniformly throughout the internal pores. The nanomaterial can be disposed in the middle of the monolith. In addition, a method for making a monolithic solid with both high surface area and good bulk electrical conductivity is provided. A porous substrate with a thickness of 100 micrometers or more and macropores throughout its thickness is prepared. At least one catalyst is deposited inside the porous substrate. Chemical vapor deposition is then used to uniformly deposit a nanomaterial in the macropores throughout the thickness of the porous substrate. Applications include electrical energy storage, such as batteries and capacitors, and hydrogen storage.

Spatial Clustering of Pixels of a Multispectral Image
James Lynn Conger
U.S. Patent 8,811,754 B2
August 19, 2014
A system for clustering the pixels of a multispectral image is provided. The clustering system computes a maximum spectral similarity score for each pixel, which indicates the similarity between that pixel and the most similar neighbor. To determine the maximum similarity score for a pixel, the clustering system generates a similarity score between that pixel and each of its neighboring pixels and selects the similarity score that represents the highest similarity as the maximum similarity score. The system may apply a filtering criterion based on the maximum similarity score so that pixels with similarity scores below a minimum threshold are not clustered. The system changes the current values of the pixels in a cluster based on an average of the original values of the cluster’s pixels.

Targeted Antimicrobials and Related Compositions, Methods and Systems
Paul J. Jackson, Brian E. Souza, Feliza A. Bourguet, Matthew A. Coleman
U.S. Patent 8,821,860 B2
September 2, 2014
Targeted antimicrobials are described as well as related compositions, methods, and systems.

Systems and Methods of Varying Charged Particle Beam Spot Size
Yu-Jiuan Chen
U.S. Patent 8,822,946 B2
September 2, 2014
These devices enable shaping of a charged-particle beam. A modified dielectric wall accelerator includes a high-gradient lens section and a main section. The high-gradient lens section can be dynamically adjusted to establish the desired electric fields to minimize undesirable transverse defocusing fields at the entrance to the dielectric wall accelerator. Once a baseline setting with the desired output beam characteristic is established, the beam’s characteristics can be varied by slightly adjusting the electric fields established across different sections of the modified dielectric wall accelerator. The beam’s shape can also be controlled by introducing intentional timing desynchronization offsets and producing an injected beam that is not fully matched to the entrance of the modified dielectric accelerator.

Passive Magnetic Bearing System
Richard F. Post
U.S. Patent 8,823,233 B2
September 2, 2014
An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive–active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation require only a single cylindrical Halbach array for operation and thus are especially suited for use in high-rotation-speed applications, such as flywheel energy storage systems. Eliminating the need for an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation in the magnetic field strength of permanent magnets in the levitating magnet arrays.

Web-Based Emergency Response Exercise Management Systems and Methods Thereof
John W. Goforth, Michael B. Mercer, Zach Heath, Lynn I. Yang
U.S. Patent 8,827,714 B2
September 9, 2014
This method simulates portions of an emergency response exercise by generating situational awareness outputs associated with a simulated emergency and sending those outputs to multiple output devices. The method also sends decisions associated with the situational awareness outputs at a decision point to a user device and receives a selected decision from the user. It then generates new situational awareness outputs based on the selected decision and repeats the sending, outputting, and receiving steps based on the new situational awareness outputs. Other methods, systems, and computer program products are included.

Method and System for Polishing Materials Using a Nonaqueous Magnetorheological Fluid
Joseph Arthur Menapace, Paul Richard Ehrmann
U.S. Patent 8,828,262 B2
September 9, 2014
A nonaqueous magnetorheological fluid includes a primarily organic carrier liquid and magnetizable particles. The fluid also includes a buffer, a stabilizer, and water, and it has a pH between 6.5 and 9.0.

Use of Carbonates for Biological and Chemical Synthesis
Gregory Hudson Rau
U.S. Patent 8,828,706 B2
September 9, 2014
This system uses carbonates, especially water-insoluble or sparing soluble mineral carbonates, to maintain or increase dissolved inorganic carbon concentrations in aqueous media. In particular, the system generates concentrated dissolved inorganic carbon substrates for photosynthetic, chemosynthetic, or abiotic chemical production of carbonaceous or other compounds in solution. In some embodiments, the invention can also enhance the dissolution and retention of carbon dioxide in aqueous media and can produce pH buffering capacity, metal ions, and heat, which can be beneficial to the preceding syntheses.

Disposable and Removable Nucleic Acid Extraction and Purification Cartridges for Automated Flow-Through Systems
John Frederick Regan
U.S. Patent 8,828,716 B2
September 9, 2014
Removable cartridges are used on automated flow-through systems to extract and purify genetic material from complex matrices. Different types of cartridges are paired with specific automated protocols to concentrate, extract, and purify pathogenic or human genetic material. Their flow-through nature allows large quantities of sample to be processed. Matrices may be filtered using size exclusion or affinity filters to concentrate the pathogen of interest. Lysed material is ultimately passed through a filter to remove the insoluble material. The soluble genetic material is then delivered past a silicalike membrane that binds the genetic material, where it is washed, dried, and eluted. Cartridges are inserted into the housing areas of flow-through automated instruments, which are equipped with sensors to ensure proper placement and usage of the cartridges. Properly inserted cartridges create fluid- and air-tight seals with the flow lines of an automated instrument.

Ultraviolet Radiation Detector and Dosimeter
Craig F. Smith, Vladimir Ryzhikov, Sergei Naydenov, Dennis Wood, Volodymyr Perevertailo
U.S. Patent 8,829,457 B2
September 9, 2014
An ultraviolet radiation dosimeter apparatus measures an individual’s radiation exposure from incoming ultraviolet rays. The device includes a dosimeter body with an ultraviolet filter and a detector semiconductor substrate for detecting incoming ultraviolet rays and producing a signal. The semiconductor substrate is made of zinc–selenium(tellurium). A chip in the dosimeter body receives the signal and measures the individual’s exposure from the incoming ultraviolet rays.

Three-Dimensional Boron Particle Loaded Thermal Neutron Detector
Rebecca J. Nikolic, Adam M. Conway, Robert T. Graff, Joshua D. Kuntz, Catherine Reinhardt, Lars F. Voss, Chin Li Cheung, Daniel Heineck
U.S. Patent 8,829,460 B2
September 9, 2014
Three-dimensional, boron-particle-loaded, thermal neutron detectors use neutron-sensitive conversion materials in the form of nanopowders and micrometer-sized particles, rather than other approaches such as thin films, suspensions, and paraffin. Methods are used to infiltrate, intersperse, and embed the neutron nanopowders to form two- or three-dimensional charge-sensitive platforms. The use of nanopowders enables conformal contact with the entire charge-collecting structure regardless of its shape or configuration.

Methods and Systems for Raman and Optical Cross-Interrogation in Flow-Through Silicon Membranes
Tiziana C. Bond, Sonia E. Letant
U.S. Patent 8,830,450 B2
September 9, 2014
Cross-interrogating photonic detection systems and methods are shown. A flow-through photonic crystal membrane with a surface-enhanced Raman scattering (SERS) substrate is provided with pores distributed along multiple regions. The pores of one region have walls to which a first type of target-specific anchor can be attached, while pores of another region have walls to which a second type of target-specific anchor can be attached. An optical arrangement out of plane to the SERS substrate is also provided for enhanced sensitivity and identification of target organisms.

Separation of a Target Substance from a Fluid or Mixture Using Encapsulated Sorbents
Roger D. Aines, Christopher M. Spadaccini, Joshuah K. Stolaroff, William L. Bourcier, Jennifer A. Lewis, Eric B. Duoss, John J. Vericella
U.S. Patent 8,834,605 B2
September 16, 2014
This apparatus separates a target substance from a fluid or mixture using capsules with a coating and encapsulated stripping solvents. The coating is permeable to the target substance. When the capsules are exposed to the fluid or mixture, the target substance migrates through the coating and is taken up by the stripping solvents. The substance is separated from the fluid or mixture by driving it from the capsules.

Bio-Threat Microparticle Simulants
George Roy Farquar, Roald Leif
U.S. Patent 8,835,178 B2
September 16, 2014
A biothreat simulant includes a carrier with encapsulated DNA. Steps are described for encapsulating DNA into the carrier to produce a biothreat simulant.

Mixed Crystal Organic Scintillators
Natalia P. Zaitseva, M. Leslie Carman, Andrew M. Glenn, Sebastien Hamel, Robert Hatarik, Stephen A. Payne, Wolfgang Stoeffl
U.S. Patent 8,835,865 B2
September 16, 2014
A mixed organic crystal includes a single mixed crystal with two compounds and different bandgap energies. The organic crystal exhibits a signal response signature for neutrons from a radioactive source. This signature does not include a significantly delayed luminescence characteristic of neutrons interacting with the organic crystal, relative to the luminescence that characterizes gamma rays interacting with the organic crystal. In one configuration, the organic crystal includes bibenzyl and stilbene or a stilbene derivative, and it exhibits a signal response signature for neutrons from a radioactive source.

Initiation Disruptor Systems and Methods of Initiation Disruption
Dennis W. Baum
U.S. Patent 8,839,704 B2
September 23, 2014
An initiation disruption system includes an explosive charge, a plurality of particles in a layer at least partially surrounding the explosive charge, and a fire suppressant adjacent to the particles. One method for disabling an object is to place the system near that object, initiating the explosive charge and thereby applying mechanical loading to the object so that the object is disabled. In another design, a device has a plurality of particles bound by a binder, thereby defining a sidewall with an interior for receiving an explosive, and a fire suppressant adjacent to the particles and binder.

Silica Extraction from Geothermal Water
William L. Bourcier, Carol J. Bruton
U.S. Patent 8,840,859 B2
September 23, 2014
This method produces silica from geothermal fluid containing a low concentration of the silica (less than 275 parts per million). Steps include treating the geothermal fluid by reverse osmosis, seasoning the fluid to produce a slurry with precipitated colloids that contain the silica, and separating the silica from the slurry.

Emergency Sacrificial Sealing Method in Filters, Equipment, or Systems
Erik P. Brown
U.S. Patent 8,844,938 B2
September 30, 2014
A system seals a filter or equipment component to a base and will continue to seal the filter or equipment component to the base in the event of hot air or a fire. The system includes a first sealing material between the filter or equipment component and the base, and a second sealing material between the filter or equipment component as well as the base and proximate the first sealing material. The first and second sealing materials are positioned relative to each other and relative to the filter or equipment component and the base to seal the filter or equipment component to the base. In the event of a fire, the second sealing material will be activated and will expand to seal the filter or equipment component to the base.

Real-Time System for Imaging and Object Detection with a Multistatic GPR Array
David W. Paglieroni, N. Reginald Beer, Steven W. Bond, Philip L. Top, David H. Chambers, Jeffrey E. Mast, John G. Donetti, Blake C. Mason, Steven M. Jones
U.S. Patent 8,854,248 B2
October 7, 2014

Spatially Assisted Down-Track Median Filter for GPR Image Post-Processing
David W. Paglieroni, N. Reginald Beer
U.S. Patent 8,854,249 B2
October 7, 2014
A real-time imaging system detects the presence of subsurface objects within a medium. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals that travel down the surface and are generated by an array of transceiver antenna pairs positioned across the surface. The system preprocesses the return signals to suppress certain undesirable effects. The system produces synthetic aperture radar images from real aperture radar images generated from the preprocessed return signal. The system then postprocesses the synthetic aperture radar images to improve detection of subsurface objects. The system identifies peaks in the energy levels of the postprocessed image frame, which indicate the presence of a subsurface object.

Tracking Target Objects Orbiting Earth Using Satellite-Based Telescopes
Willem H. De Vries, Scot S. Olivier, Alexander J. Pertica
U.S. Patent 8,862,398 B2
October 14, 2014
A system for tracking objects in Earth’s orbit uses a constellation or network of satellites featuring imaging devices. An object-tracking system includes a ground controller and, for each satellite in the constellation, an onboard controller. The ground controller receives ephemeris information for a target object and directs that information to the satellites. Each onboard controller receives ephemeris information for a target object, collects images of the object based on the expected location of the object at an expected time, identifies actual locations of the object from the collected images, and identifies a next-expected location based on the identified actual locations of the object. The onboard controller processes the collected image to identify the actual location of the target object and transmits that location information to the ground controller.

High Speed, Real-Time, Camera Bandwidth Converter
Dan E. Bower, David A. Bloom, James R. Curry
U.S. Patent 8,866,915 B2
October 21, 2014
Image data from a complementary metal-oxide semiconductor sensor with 10-bit resolution is reformatted in real time to allow the data to stream through communications equipment that is designed to transport data with 8-bit resolution. The incoming image data have 10-bit resolution. The communication equipment can transport image data with 8-bit resolution. Image data with 10-bit resolution is transmitted in real time—without a frame delay—through the communication equipment by reformatting the data.

Tethered Catalysts for the Hydration of Carbon Dioxide
Carlos A. Valdez, Joe H. Satcher, Jr., Roger D. Aines, Sergio E. Wong, Sarah E. Baker, Felice C. Lightstone, Joshuah K. Stolaroff
U.S. Patent 8,877,069 B2
November 4, 2014
This system substantially increases the efficiency of carbon dioxide capture and removal by positioning a catalyst within an optimal distance from the air–liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst, and this tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

Methods and Systems Using Encapsulated Tracers and Chemicals for Reservoir Interrogation and Manipulation
Jeffery Roberts, Roger D. Aines, Eric B. Duoss,Christopher M. Spadaccini
U.S. Patent 8,877,506 B2
November 4, 2014
This apparatus, method, and system are used for reservoir interrogation. A tracer is encapsulated in a receptacle. The receptacle containing the tracer is injected into the reservoir. The tracer is analyzed for reservoir interrogation.

Ultrafast Transient Granting Radiation to Optical Image Converter
Richard E. Stewart, Stephen P. Vernon, Paul T. Steel, Mark E. Lowry
U.S. Patent 8,879,137 B2
November 4, 2014
A high-sensitivity, ultrafast transient-grating radiation-to-optical image converter is based on a fixed transmission grating adjacent to a semiconductor substrate. X rays or optical radiation passing through the fixed transmission grating is thereby modulated and produces a small periodic variation of refractive index or transient grating in the semiconductor through carrier-induced refractive index shifts. An optical or infrared probe beam tuned just below the semiconductor bandgap is reflected off a high-reflectivity mirror on the semiconductor so that the beam double passes and interacts with the radiation-induced phase grating therein. A small portion of the optical beam is diffracted out of the probe beam by the radiation induced transient grating to become a converted signal imaged onto a detector.

System for Closure of a Physical Anomaly
Jane P. Bearinger, Duncan J. Maitland, Daniel L. Schumann, Thomas S. Wilson
U.S. Patent 8,882,786 B2
November 11, 2014
These systems are used for closure of a physical anomaly. Closure is accomplished by a closure body with an exterior surface. The exterior surface contacts the opening of the anomaly and then closes the anomaly. The closure body has a primary shape for closing the anomaly and a secondary shape for being positioned in the physical anomaly. The closure body preferably comprises a shape memory polymer.

Development of an Electronic Device Quality Aluminum Antimonide (AlSb) Semiconductor for Solar Cell Applications
John W. Sherohman, Jick Hong Yee, Arthur W. Combs, III
U.S. Patent 8,883,548 B2
November 11, 2014
Electronic-device-quality aluminum antimonide– (AlSb-) based single crystals produced by controlled atmospheric annealing are used in various configurations for solar-cell applications. The AlSb-based solar cell device provides direct conversion of solar energy to electrical power.

Nanolipoprotein Particles and Related Compositions, Methods, and Systems
Paul D. Hoeprich, Nicholas O. Fischer, Peter W. Mason, Craig D. Blanchette
U.S. Patent 8,883,729 B2
November 11, 2014
A functionalized nanolipoprotein particle uses an anchor substrate compound for binding with a corresponding anchor compound on a target molecule.

Post Polymerization Cure Shape Memory Polymers
Thomas S. Wilson, Michael Keith Hearon, Jane P. Bearinger
U.S. Patent 8,883,871 B2
November 11, 2014
This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape-memory behavior. They can first be polymerized to a linear or branched polymeric structure and, with their thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions. They are then linked to a shape-memory thermoset polymer retaining the processed shape.

Gamma Ray Spectroscopy Employing Divalent Europium-Doped Alkaline Earth Halides and Digital Readout for Accurate Histogramming
Nerine Jane Cherepy, Stephen Anthony Payne, Owen B. Drury, Benjamin W. Sturm
U.S. Patent 8,884,233 B2
November 11, 2014
A scintillator radiation detector system, according to one embodiment, includes a scintillator and a processing device for processing pulse traces corresponding to light pulses from the scintillator, wherein pulse digitization is used to improve energy resolution of the system. A scintillator radiation detector system, according to another embodiment, includes a processing device for fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times and performing a direct integration of fit parameters. A method, according to yet another embodiment, includes processing pulse traces corresponding to light pulses from a scintillator, wherein pulse digitization is used to improve energy resolution of the system. In a further embodiment, a method includes fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times and performing a direct integration of fit parameters. Additional systems and methods are also presented.

Alkali Resistant Optical Coatings for Alkali Lasers and Methods of Production Thereof
Thomas F. Soules, Raymond J. Beach, Scott C. Mitchell
U.S. Patent 8,889,251 B2
November 18, 2014
In one embodiment, a multilayer dielectric coating for use in an alkali laser includes two or more alternating layers of high- and low-refractive index materials, wherein an innermost layer includes a layer thicker than 500 nanometers and less dense than 97 percent of a theoretical layer of the elements of alumina, zirconia, or hafnia for protecting subsequent layers of the two or more alternating layers of high- and low-index dielectric materials from an alkali attack. In another embodiment, a method for forming an alkali-resistant coating includes forming a first oxide material above a substrate and forming a second oxide material above the first oxide material to form a multilayer dielectric coating, wherein the second oxide material is on a side of the multilayer dielectric coating for contacting an alkali.

Immunostimulatory Nanoparticles and Related Compositions, Methods, and Systems
Paul D. Hoeprich, Nicholas O. Fischer, Craig Blanchette, Peter W. Mason
U.S. Patent 8,889,623 B2
November 18, 2014
Provided herein are immunostimulatory nanolipoprotein particles and related compositions, methods, and systems.

Fission Meter and Neutron Detection Using Poisson Distribution Comparison
Mark S. Rowland, Neal J. Snyderman
U.S. Patent 8,891,720 B2
November 18, 2014
This neutron detector system and method discriminates fissile material from nonfissile material, wherein a digital data-acquisition unit collects data at a high rate and in real time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from an unknown source and detecting excess grouped neutrons to identify fission in the unknown source. Comparison of the observed neutron count distribution with a Poisson distribution is performed to distinguish fissile material from nonfissile material.