Portable Isotope Neutron Spectrometry

    A mechanically cooled and field-ready gamma spectrometer (ORTECtrans-SPEC-N) was used.

    ·No californium-252 source required.

    ·Automatic analysis of chemicals.

    ·Use a portable small neutron generator, which greatly saves weight, power consumption and space.

    ·Rugged laptop comes with chemical analysis and identification software.

    ·External rechargeable battery supports 12 hours of continuous power supply.

    ·Ultra-light carbon fiber measurement bracket.

    ·USB and power cord.

    · Security suite.

    ·Reinforced wheeled transport box.

    ORTECPINS3-CW is a portable isotope neutron spectroscopy (PINS) non-destructive evaluation system that analyzes and provides on-site identification information on the composition of unidentified or suspicious chemicals inside unopened thick steel containers. Designed to identify chemicals within a container without the need for disassembly, contact, physical sampling or closure of the container, the system is widely deployed in various locations as part of the nation's anti-terrorism apparatus, providing a secure method of identifying "suspicious" packaging contents.

    PINS3-CW is easy to use with the ORTECtrans-SPEC-N mechanically cooled high-purity germanium spectrometer. trans-SPEC-N has been specifically designed and tested to replace existing liquid nitrogen-cooled detectors currently used in neutron chemical analysis systems and provide essential in-situ spectral data for non-invasive chemical identification.

    PINS3-CW provides significant advantages over previous liquid nitrogen design systems by eliminating logistical and safety issues associated with liquid nitrogen storage and transportation, equipment handling, maintenance and training.

    PINS application

    ·Ammunition-artillery, rockets, explosives, landmines

    ·Containers - cylinders, tanks, bags, briefcases, parcels.

    ·Chemicals - chemical warheads, gases, smoke.

    PINS overview

    The Portable Isotope Nuclear Spectroscopy (PINS) Chemical Identification System non-destructively identifies hazardous compounds and mixtures. There is no need to open or touch the test object, greatly increasing safety. As shown in the figure, PINS uses neutrons to detect test objects. The neutrons excite the interior of the atomic nucleus, causing the excited nuclei to produce gamma rays. Each chemical element's gamma rays have a unique energy intensity pattern, or spectrum, so by analyzing the gamma ray spectrum, PINS software can identify chemical elements within a test object and determine whether the object contains chemical warfare agents, fillers (such as sand), or smoke-producing chemicals.

    Working principle

    PINS3-CW uses neutrons produced by a neutron generator to excite atomic nuclei within the object being measured. The fusion of deuterium atoms (D+D) within the neutron generator will result in the formation of He-3 ions and neutrons with a kinetic energy of approximately 2.5 MeV. The standard PINS3-CW neutron generator can produce 10 million neutrons per second. The generator fires neutrons in all directions, with approximately 1,000 neutrons per second striking each square centimeter of the test object's surface. Because neutrons are a highly penetrating form of radiation, most neutrons will pass through the test object's outer shell and interact with the chemicals inside.

    Neutrons from the generator excite the nuclei they encounter through inelastic scattering or neutron capture. In either case, excited nuclei decay to their ground state by emitting gamma rays, which are characteristic of emitting nuclei. That is, gamma ray energy and intensity often vary greatly from one type of nucleus to another. For example, hydrogen nuclei emit 2.2-MeV gamma rays when bombarded by neutrons, while phosphorus nuclei emit 1.3-MeV gamma rays.

    Neutron-induced gamma rays are measured by a high-purity germanium (HPGe) spectrometer and classified into spectra by the spectrometer electronics. By analyzing the spectrum, the chemical elements excited by the neutrons can be determined and the chemicals within the test object can be identified.

    Run PINS

    Developed specifically for field deployment, PINS3-CW is portable and rugged. Its components include a mechanically cooled spectrometer with integrated multi-channel analyzer, neutron generator, detector holder and shield, as well as a laptop computer for user interface. Custom software displays data in real time as it is collected and provides comprehensive monitoring and analysis options.

    Laptop used as PINS3-CW control panel. The computer allows the user to initialize the instrument, start and stop data acquisition by the gamma-ray spectrometer, display and analyze the resulting gamma-ray spectrum. The connecting cable, 82 feet (25 meters) long, keeps the computer a safe distance from the radiation isolation zone and provides communication between the computer, gamma-ray spectrometer and neutron generator.

    Trans-SPEC-N mechanically cooled high-purity germanium spectrometer

    Unlike the liquid nitrogen-cooled HPGe spectrometer used in previous PINS systems, PINS3-CW uses trans-SPEC-N to mechanically cool the HPGe spectrometer, which does not require liquid nitrogen. The electrical energy required to cool the spectrometer detector is approximately 30 watts. The trans-SPEC-N lithium-ion battery keeps the detector cool for 10 to 12 hours, and the external battery supports "hot swapping" for extended use of the instrument in the field. trans-SPEC-N provides a flexible, modular solution to support on-site detection of chemicals with the following features:

    ·LN2-free - Miniature, high-reliability, "always-on" Stirling cycle refrigerator does not require liquid nitrogen; the detector element is packaged in a high-reliability, low-loss, all-metal sealed cryostat.

    · High sensitivity - large (>50% relative efficiency) HPGe detector.

    ·High Stability - Digital electronics provide solutions for troublesome analysis under harsh conditions.

    ·Bright and clear - VGA resolution display and touch-sensitive operation screen.

    ·Integrated integrated design - sturdy and compact, no interconnection required - easy to install and use.

    ·Intelligent - nuclide identification and activity calculation for nine regions of interest (ROI).

    ·Reliable connection - USB2.0 and wireless.

    · 802.11 communications, built-in GPS and secure digital input/output (SDIO) storage of collected spectra.

    Flexible - Works with a variety of power sources including internal battery, auxiliary external battery, car battery (any 12VDC) and line power; switches automatically.

    electronic neutron generator

    The P385 neutron generator adopts a new generation of digital control technology. Operating options are integrated into the PINSPlus analysis software and include start and stop settings; run timer and on/off indication. The P385 has a wide range of safety features. There are built-in key locks and external interlocks, while smart lights sense light and current. The P385 is designed to extend service life and save life cycle costs. The accelerator head contains longer-lasting tubes than other neutron generators on the market. The portable neutron generator continues the design of flexible modular solutions to support on-site detection of chemical threats with the following features:

    ·Longer tube life - reduced life cycle costs.

    ·Higher output - increased recognition time.

    ·Modern digital control technology - integrated with PINSPlus analysis software.

    ·Integrated high-voltage power supply - convenient on-site power supply.

    Automated analysis of chemicals

    The PINS data acquisition program records and displays spectral measurements from trans-SPEC-N. It also analyzes spectra recorded every 10 seconds, fits peaks of interest, recalibrates the energy scale and performs chemical analysis. The new chemical analysis method is based on the decision tree logic shown and identifies chemicals within the object being measured. The new probabilistic method traces each path in the decision tree and assigns a score to each chemical it may contain. Chemicals with a score are selected as included chemicals.

    New chemical analysis methods are faster, more accurate, and more easily expand the list of chemicals that PINS can automatically identify. Currently, PINS automatic analysis software can identify the following chemicals.