Journal Club presentation Helena Pikhartova March 14, 2018 2/8 - - PowerPoint PPT Presentation

Journal Club presentation

Helena Pikhartova March 14, 2018

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Summary of article

Low-dose active detection technique using interactions of multi-MeV mono-energetic photons and neutrons. ✽ measuring material’s areal density and effective atomic number ✽ confirming presence of fissionable materials ”We demonstrated a novel modality of imaging that employs a source of photons and neutrons based on low-energy nuclear reactions. The high energy of the produced photons and the multi-modality of the source enables dual and multi-energy transmission radiography as a method to achieve contrast among different elements, while simultaneously inducing fission signatures needed to confirm the presence of materials that could be used in construction of a nuclear explosive.”

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Cargo scanning

Image source: Varian medical systems

Types of scanners: Active: ✽ Gamma-ray radiography ✽ X-ray radiography ✽ Dual-energy X-ray radiography ✽ Backscatter X-ray radiography ✽ Neutron activation systems Passive: ✽ Muon tomography ✽ Gamma radiation detectors ✽ Neutron radiation detectors ✽ Gamma spectroscopy Cargo containers are scanned at ports and border crossings.

Image: dutch.euro

Usually scans need to be completed within couple tens of seconds while vehicles move.

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Setup

Ion accelerator: ✽ RF quadrupole accelerator ✽ 3-MeV D+ beam → boron target → emission of energetic neutrons and gamma rays at 4.438MeV and 15.1MeV Detectors: ✽ Gamma ray detector - Cherenkov detectors ✽ Neutron detectors - liquid scintillator and composite scintillation detector

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Results - transmission imaging

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Results - delayed neutron emission

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Related work

PB Rose Jr, AS Erickson ­ Journal of Applied Physics, 2016 ­ aip.scitation.org Cherenkov detectors can offer a significant advantage in spatial imaging applications when excellent timing response, low noise and cross talk, large area coverage, and the ability to

• perate in magnetic fields are required. We show that an array of Cherenkov detectors with

Cited by 1 Related articles All 4 versions Web of Science: 1 M Mayer, J Nattress, I Jovanovic ­ Applied Physics Letters, 2016 ­ aip.scitation.org Detection of unique signatures of special nuclear materials is critical for their interdiction in a variety of nuclear security and nonproliferation scenarios. We report on the observation of delayed neutrons from fission of uranium induced in dual­particle active interrogation based Cited by 1 Related articles All 5 versions Web of Science: 1 J Harms, PB Rose, A Erickson ­ IEEE Sensors Journal, 2017 ­ ieeexplore.ieee.org In imaging arrays, the sensors are typically packed as tightly as possible to maximize spatial resolution, which leads to detector­to­detector scatter, or cross talk, adding to image noise and hindering contrast. In this paper, we compare custom­made quartz­based Cherenkov Cited by 1 Related articles All 2 versions KB Pfeifer, KE Achyuthan, M Allen… ­ Journal of radiation …, 2017 ­ academic.oup.com Abstract Neutron sensing is critical in civilian and military applications. Conventional neutron sensors are limited by size, weight, cost, portability and helium supply. Here the microfabrication of gadolinium (Gd) conversion material–based heterojunction diodes for Related articles All 10 versions K Ogren, J Nattress, I Jovanovic ­ AIP Advances, 2018 ­ aip.scitation.org Measurements of the geometric configuration of objects and their material composition are needed for nuclear treaty verification purposes. We experimentally demonstrate a simple method based on monoenergetic fast neutron transmission to realize crude imaging of the Related articles All 3 versions C Geddes, B Ludewigt, J Valentine, B Quiter… ­ 2017 ­ osti.gov Executive Summary Near= monoenergetic photon sources (MPSs) have the potential to improve sensitivity at greatly reduced dose in existing applications and enable new capabilities in other applications, particularly where passive signatures do not penetrate or Related articles J Nattress, I Jovanovic ­ Nuclear Instruments and Methods in Physics …, 2017 ­ Elsevier Abstract We present a calibration method for an organic scintillator suitable for gamma energies of up to 15 MeV. We use a combination of experiments and simulations to identify prominent features in the light output spectra to provide an accurate calibration method over Related articles

Cherenkov detectors for spatial imaging applications using discrete­energy photons Detection of special nuclear material from delayed neutron emission induced by a dual­ particle monoenergetic source Characterization of ­Ray Cross Talk in Cherenkov­Based Detectors for Active Interrogation Imaging Applications Microfabrication of a gadolinium­derived solid­state sensor for thermal neutrons Spectroscopic fast neutron transmission imaging in a treaty verification setting Impact of Monoenergetic Photon Sources on Nonproliferation Applications Final Report Response and calibration of organic scintillators for gamma­ray spectroscopy up to 15­ MeV range

Different detection methods or improvements of photon and neutron detectors. Aiming for higher accuracy in detecting geometry, composition and fissile mass.

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The end of presentation

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