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Kerr, Phil L.

Publications and source records attributed to Kerr, Phil L..

9 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Neutron inelastic scattering measurements on KCl and NaCl samples at the Dome

Precise and accurate measurements of neutron inelastic scattering cross sections are vital for both the LLNL national security mission and for scientific applications such as the nuclear spectroscopy of planetary bodies. In this work, initial measurements of relative cross sections were performed by irradiating KCl and NaCl samples with a DD neutron generator, a DT neutron generator, and a PuB source in building 262, the Dome. The measurements allowed the existing experimental setup to be benchmarked. Several improvements to the setup are suggested for future experiments.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2023

Verification of Spent Fuel Inside Dry Storage Casks by Cask Top Fast Neutron Mapping (FY2023 Mid-Year Report)

This project is developing a prototype scanner array verification system for detection of missing fuel assemblies in spent-fuel storage casks. The prototype consists of six fast-neutron scintillator detectors mounted to a linear actuator frame that is placed on the top of a spent fuel cask to scan across all fuel assembly positions. The scanner array was assembled and tested at LLNL in FY2022. A field test schedule has been requested at the Idaho National Laboratory (INL) Cask Farm site for FY2023. Note that the Cask Farm contractor determines this scheduling and not INL directly. Further system automation will be designed and implemented with the goal of obtaining a level of system operation that meets IAEA needs. This includes integration of the scanner array and data-acquisition control software into a single interface for operator use. In addition, commercial operators and the IAEA may have special requirements for portability, shipping, lifting, and installation. Prior to the Field Test at INL, the system will be operated at LLNL to exercise lifting procedure and linear actuators, monitor stability of detector energy and pulse-shape discrimination calibration, and test system software integration efforts. Following the Field Test, we will present results and discuss the technology with the IAEA. We will incorporate additional improvements to the system based on lessons learned from the field test and feedback from the IAEA. If successful, the technology can be transferred to the IAEA or other stakeholders for assessment.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Verification of Spent Fuel Inside Dry Storage Casks by Fast/Epi-thermal Neutron Mapping (FY2022 NA-241 Annual Report)

Development of a spent-fuel verification method based upon positional measurement of fast neutrons emitted from the top surface of the dry storage casks. A proof-of-principle field test on a partially loaded spent-fuel cask will be conducted by measuring the fast neutron flux on the top of the cask as a function of position using a single detector. If a useful verification signature is demonstrated, a multidetector scanning array will be built and tested to demonstrate a practical rapid verification system.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Verification of Spent Fuel Inside Dry Storage Casks Using Neutron Mapping (2022 Midyear Report)

Development of a spent-fuel verification method based upon positional measurement of fast neutrons emitted from the top surface of the dry storage casks. A proof-of-principle field test on a partially loaded spent-fuel cask will be conducted by measuring the fast neutron flux on the top of the cask as a function of position using a single detector. If a useful verification signature is demonstrated, a multi-detector scanning array will be built and tested to demonstrate a practical rapid verification system.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2021

Report on Field Test at INL Cask Farm of Single Detector Fast Neutron Spent Fuel Cask Verification System

Detecting diversion of spent fuel elements in dry storage casks is challenging due to the thick shielding used in cask construction. Measurements on top of the cask to map the underlying arrangement of the fuel elements and looking for anomalous changes over time has proven difficult to achieve using gamma rays due to the high scattering and attenuation from the thick steel structure, weakening information on the present or absence of fuel bundles. Simulations and laboratory experiments suggest that the high-energy neutron flux (>200 keV) measured directly above each fuel bundle is sufficient to produce a position map that enables detection of the present or absence of fuel bundles, and therefore diversion of a spent fuel bundle. A single-detector spent-fuel monitoring technique based on this principle was development at the Lawrence Livermore National Laboratory (LLNL). The INL Cask Farm in the INTEC technical area at Idaho National Laboratory (INL) offers the capability to test this technique on an MC-10 storage cask which has a distribution of full and empty fuel positions. An experimental test plan for the single-detector verification system was developed in consultation with INL personnel to be completed in FY2021. Due to travel advisories related to COVID-19, the experimental test plan was adapted to enable INL personnel to carry out the measurements in consultation with LLNL personnel following shipment of the LLNL system to INL. Field test measurements of the single detector verification system were successfully carried out at the INL cask farm on September 7-9, 2021. This document summarizes results of the field test.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2020

Verification of Spent Fuel Inside Dry Storage Casks by Fast/Epi-thermal Neutron Mapping: FY2020 Annual Report to NA241 (Annual Report)

Lawrence Livermore National Laboratory has embarked upon development of a novel methodology for verification of spent fuel inside dry storage casks. The issue of verification of the integrity of spent fuel inside dry storage has been one of the most challenging technical problems facing IAEA for many decades. The difficulty arises because of the massive amount of shielding between the inner spent fuel and the outer surface where measurements can be performed. Despite many efforts, detection of useful gamma rays or neutrons from the outer surface has so far proven unsuccessful.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

IER-407 CED-3b Rev-1: Experiment Execution Report for the Inherently Safe Subcritical Assembly (ISSA) Subcritical Measurements

This set of benchmark subcritical multiplicity experiments was conducted at the ISSA experiment center of Lawrence Livermore National Laboratory. The purpose of these subcritical experiments, as described in the ISSA final design report, was to measure fission neutrons by collecting time-tagged data corresponding to a maximum multiplication of approximately 20. The fission source for this experiment was Materials Test Reactor (MTR)-type highly enriched uranium fuel assembly, which is composed of nineteen fuel plates. One, two, four, six and nine ISSA fuel assemblies were closely packed and loaded inside a support fixture assembly and immersed in water. Four 3 He proportional counters were placed around the fuel assemblies, and list-mode experimental data was taken. Additionally, efficiency calibration measurements with calibrated neutron sources were conducted. The LLNL developed codes BIGFIT and OSANTI RESTART will be used to evaluate the measured data and calculate the experimental multiplication.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Pillar-structured neutron detector based multiplicity system

This work demonstrates the potential of silicon pillars filled with boron-10 as a sensor technology for a compact and portable neutron multiplicity system. Solid-state, semiconductor based neutron detectors may enable completely new detector form factors, offer an alternate approach to helium-3 based systems, and reduce detector weight and volume requirements. Thirty-two pillar-structured neutron detectors were assembled into a system with an active area of over 20 cm 2 and were used in this work to demonstrate the feasibility of this sensor technology as a potential replacement for helium-3 based gas detectors. Multiplicity measurements were successfully carried out using a californium-252 neutron source, in which the source mass, system efficiency, and die-away time were determined. As a result, this demonstration shows that these solid-state detectors could allow for a more compact and portable system that could be used for special nuclear material identification in the field.

42 ENGINEERING↗