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Both high-fidelity & toy simulations are being used to understand measured signals and improve the Area 11 NDSE diagnostic. We continue to gain more and more confidence in the ability for MCNP to simulate neutron and photon transport from source to radiation detector.
The UDCM is a low current measurement device designed to record pico-amp to micro-amp currents from radiation detectors. The UDCM is the planned replacement for the IAEA’s obsolete MiniGRAND data acquisition module. Preliminary testing of the UDCM at the IAEA facilities lead to the following recommendations from the IAEA: Increase the measurement range. Lower range by a factor of 5 and upper range by 2 orders of magnitude; Modifications to the web interface; Increase programmable acquisition time to 3600s; Develop a method to handle current offsets and negative current; Error checking when writing data to the uSD card; and Writing BID files along with the currently stored BI0 files.
In implementation of nuclear safeguards, many different techniques are being used to monitor operation of nuclear facilities and safeguard nuclear materials, ranging from radiation detectors, flow monitors, video surveillance, satellite imagers, digital seals to open source search and reports of onsite inspections/verifications. Each technique measures one or more unique properties related to nuclear materials or operation processes. Because these data sets have no or loose correlations, it could be beneficial to analyze the data sets together to improve the effectiveness and efficiency of safeguards processes. Advanced visualization techniques and machine-learning based multi-modality analysis could be effective tools in such integrated analysis. In this project, we will conduct a survey of existing visualization and analysis techniques for multi-source data and assess their potential values in nuclear safeguards.
Dr. Raymond R. Raylman, Professor and Vice Chair for Research, Radiology Department at WVU was the Principal Investigator for the project. The Jefferson Lab partner on this project was the Radiation Detector and Imaging Group in the Physics Division, led by Dr. Drew Weisenberger who was the coordinator of the project execution and the chief contact with WVU. The responsibility of Jefferson Lab was to facilitate optimization of data acquisition software, conversion of JLab Fortran iterative positron emission mammography computer code to C++ and to act as a computer code repository. During the two year project interactions and exchange of information was directed by Dr. Raylman and Dr. Wesienberger. WVU provided the expertise that allowed JLab to continue development of the current JLab data acquisition software referred to as JDAQ. JDAQ is a highly flexible Java language based data acquisition tool that helps to minimize software induced dead-time while maintaining the highest possible data rates from a JLab built FPGA based analog-to-digital convertor (ADC). JDAQ interfaces directly with the FPGA based multi-channel ADCs. Using JDAQ it is possible process data from a number of different detector types such as the PET systems at WVU. Because of the inherent flexibility of our processing software, we are also able adjust detector readout parameters during operation to provide the best possible data presentation and calibration parameters. To accommodate the high rate nature of PET detector systems JDAQ was designed to be scalable across an Ethernet network as well as for multi-cpu computer systems, and it also has the capability to synchronize many ADCs connected to multiple computers. During the project WVU will provided iterative reconstruction algorithm expertise and Fortran programming assistance to facilitate the conversion to C++ of a JLab developed Fortran positron emission mammography (PEM) reconstruction code. Also WVU provided acceptance testing of the new C++ based PEM reconstruction code. The PEM code is a maximization (MLEM) image reconstruction program that created images from the list-mode data acquired from the PET system.
The Nuclear Inspection Node Event SIMulator (NINESIM) is a tool that is capable of modeling a node that monitors passing traffic for radiological and nuclear materials. This task requires the consideration of a number of factors. One such factor is clutter, or the level of traffic passing through a node. Clutter might affect the performance of radiation detectors due to attenuation or scattering that particles undergo as they move through the material. This paper discusses the results from MCNP simulations that were performed to determine in what scenarios clutter had a significant impact on detector performance, where the receiver operating characteristic (ROC) curve was used as the metric to evaluate detector performance. Clutter was found to have an insignificant impact on neutron detection, therefore, clutter may be ignored when modeling neutron detectors. However, there were a number of scenarios where clutter was found to affect the performance of photon detectors; the amount of traffic was found to be directly proportional to the effectiveness of photon detectors. The results of this work were then used to develop a photon clutter scaling algorithm that will be implemented into NINESIM. The Domestic Nuclear Detection Office, and possibly other agencies such as the Defense Threat Reduction Agency, will benefit from this work by eventually obtaining a tool that can enhance their ability in countering the illicit movement of radiological and nuclear materials.
The Comprehensive Nuclear-Test-Ban Treaty limits radiation measurements during an on-site inspection to those isotopes the States Parties have agreed are appropriate for the purpose of determining if a nuclear explosion has occurred without revealing irrelevant confidential information. To accomplish this, the radiation detectors used will need to have information barriers that are proven to function reliably over the wide range of possible inspection uses and scenarios. In order to provide a basis set of spectra for testing proposed information barrier systems, PNNL and LLNL defined a set of treaty-compliant and non-compliant scenarios and then independently developed a set of spectra relevant to those scenarios. Real spectra were utilized to the extent possible, but often computer simulations were necessary. These spectra will next be used to assess the performance of an INL information barrier system.
The primary goal of this project was to better understand the analytical needs of the IAEA and the applications where magnetic microcalorimeter (MMC) radiation detectors might be able to address some of these needs. In support of this, the second goal was to use MMC gamma detectors in an application of potential interest for the IAEA.
As concerns about the illicit movement of radioactive materials across international borders increase, so too has the need for increased protection of those borders both foreign and domestic. The challenge is not only to detect hidden radioactive materials, but also to distinguish them from legitimate radionuclides such as radio-pharmaceuticals that are often transported across borders and shipped throughout a country. With more than 600 U.S. border sites to protect, screening imported radioactive material requires a careful balance of high throughput and high search efficiency. However, these requirements are difficult to meet as rapid screening operations leave less time for radiation detectors to efficiently evaluate materials. In support of border security, Sandia developed organic glass scintillators.
The Radiation Detector and Imaging Group at Thomas Jefferson National Accelerator Facility (Jefferson Lab) is developing radioisotope imaging systems designed and constructed to facilitate plant biology studies at the Duke University Phytotron. The imaging systems utilize nuclear medicine imaging methodologies used in positron emission tomography (PET) and single photon emission computed tomography (SPECT) but designed specifically for plant biology. The range of plant shapes and the environmental conditions in plant growth chambers pose a technological challenge. Description: Jefferson Lab is collaborating with the Duke University Phytotron and the Triangle Universities Nuclear Laboratory (TUNL) in the construction and operation of PhytoPET and PhytoBeta (for direct beta particle detection) for plant and/or microbe imaging. The TUNL tandem Van de Graaff accelerator (maximum terminal voltage of 10 MV) has been used to generate 11C and 13N for plant biology research. The PhytoPET and PhytoBeta have been used with 11C as a 11CO2 tracer for plant ecophysiology imaging with corn, poplar, oak and barley utilizing technologies developed for nuclear physics research and nuclear medicine. The imaging detectors are based on position sensitive photomultiplier tubes coupled to scintillators. Additionally, the collaboration is investigating a methodology using single photon emitting radioisotope tracers for imaging the distribution of molecular compounds of interest in the rhizosphere, the interface between root and soil, without disturbing the root or soil habitat. Plans are underway to develop a single photon emission computed tomography (SPECT) system (PhytoSPECT) to image the bio-distribution of fungi in association with a host plant's roots. In addition to a description of the technology an overview will be given of the application of PhytoPET, PhytBeta and PhytoSPECT to plant biology research at Duke University. Conclusions: We have developed and used radioisotope imaging technologies based on PET and SPECT to visualize plant function in changing environments. There are many opportunities to provide radioisotope based imaging tools for plant ecophysiology imaging. Keywords: radioisotope detection, plant biology, carbon-11, accelerator produced isotopes
This report serves to present the evaluation results of commercial radiation detectors (SPNDs) with the potential to accomplish the data objectives—having sufficient gamma and fast neutron sensitivity—at temperatures near 650°C. The detectors chosen for evaluation are gamma ion chambers from Exosens (previously known as Photonis) models CRGA11 and CRGE32 and tantalum-based self-powered neutron detectors (Ta-SPND) from Mirion. The evaluation was performed in a series of heat irradiations from ambient to 850°C in the 9.5-inch dry tube furnace at the Ohio State University Research Reactor (OSURR). Ion chamber counting curves were measured to evaluate sensor operability at temperature. Detector sensitivity to reactor power and temperature were measured and presented in curve fit parameters. The curve fit equations were used to identify the suggested operational temperatures based on reactor power. Overall, it was evaluated that the CRGA11 was not significantly affected by temperatures up to 650°C and is operable—with higher temperature-contributed signals—up to 700°C. The CRGE32 was more affected by the high temperatures compared to the CRGA11. As a result of increasing temperature, the leakage current was a dominating factor. While the detector can operate up to 600°C and 700°C with lowered high voltage, it is not recommended unless a suitably strong gamma flux field is present. Finally, Ta SPND did not demonstrate good performance beyond 350°C due to the presence of an unknown phenomenon at changing temperatures. The study of the phenomenon is an active research topic outside the scope of this project.
Hybrid metal halides, particularly main group halide perovskites, are a unique class of materials that offer exceptional optoelectronic properties along with a remarkable materials design space. Initial research on this class of materials was driven by the ability of the prototype hybrid 3D perovskite-structured compound methylammonium lead iodide to function as the active layer in thin film solar cells. It is now known that this class of materials comprise a large family with tunable band gaps, relatively high charge carrier mobilities in both single crystal and polycrystalline forms, and relatively low concentrations of (deleterious) electrically active states within the band gap. Beyond applications in solar cells, the potential of these materials has been extended to emitters in light emitting diodes, and active components of radiation detectors. Complementing new functionality, the design space for hybrid metal halides continues to increase with discovery of new structural motifs. In this project, the combination of organic and inorganic functionalities has been employed to open pathways to the design and synthesis new, functional hybrid metal halides. Beyond the simple perovskites, Ruddlesden-Popper and Dion-Jacobsen compounds, and other variants, such as the newly advanced “hollow” perovskites have been studied. The materials have provided routes to understanding the unique electronic properties of hybrid metal halides because of their natural quantum well structures as well as other means of controlling band gaps and band dispersions. Understanding these materials, including the design rules for their formation, their structures and compositions in bulk and in thin films form, and the role of local (non-crystallographic) structure has an important aspect of this endeavor. The goal of advancing new materials and new fundamental understanding within this deceptively simple, yet fascinating class of compounds, so richly endowed with interesting and useful functionality, has been fulfilled.
During electronics testing at NSRL, the fluence/spill is recorded from the QC1 chamber. This chamber, which is a permanent fixture on the NSRL beamline, requires calibration from an external radiation detector that can measure ion flux directly. A 1.0 × 1.0 × 0.5 cm 3 scintillator is used at the testing location to calibrate all NSRL beams for electronic experiments. A calibration factor is derived by comparing the ions observed by the scintillator and QC1 during an exposure of at least 10 5 scintillator counts or total ions.
A summary of the issues that have come up in the use of the fulcrum radiation detector and the methods tools that I developed to deal with them.
Superconducting transmon qubits are a central building block of modern quantum computing architectures, yet their coherence properties remain sensitive to external influences that can limit performance or introduce temporal instabilities. In this talk, I will discuss two experimental studies aimed at quantifying these effects. First, I will examine how ionizing radiation impacts qubit relaxation. Using the same transmon device operated at two locations with dramatically different radiation backgrounds—the above-ground SQMS facility at Fermilab (USA) and the deep-underground Gran Sasso Laboratory (Italy)—we observe a higher rate of radiation-induced decay events above ground, even though intrinsic noise remains the dominant source of single-shot errors. I will also discuss the detection efficiency of a radiation detector made using such a device. Second, I will present results on how small magnetic fields, applied either during cooldown or at millikelvin temperatures, influence device stability. We find that fixed-frequency transmons maintain robust coherence up to approximately 600 mG of trapped out-of-plane field, and that controlled application of magnetic field can reduce temporal fluctuations in T1. Together, these studies provide insight into how external environments shape transmon coherence and offer potential pathways for improving qubit stability in scalable quantum processors.
The nuclear and high energy physics research community is constantly searching for new and improved tracking and radiation detectors. The introduction of micropattern detectors has opened new opportunities for improving the rate capabilities, as well as the spatial and time resolution of particle detectors in these applications. GEM detectors in particular have received enormous interest for use in detectors planned for a number of new and upgraded experiments at many different research facilities. These include both the STAR and PHENIX experiments at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, experiments at the Thomas Jefferson National Laboratory, Oak Ridge National Laboratory, and at the future electron-positron Linear Collider. At the present time, CERN is not able to supply foils in sufficient quantities to accommodate the needs of these experiments. Compounding this problem, there is a strong interest in GEM foils for numerous other applications, such as in astrophysics, medical imaging and detectors for homeland security. It would therefore be of significant benefit to the research community to develop a commercial source of GEM foils for all of these applications. Tech-Etch is in a unique position to develop this technology for commercial use. Tech-Etch has not only experience in numerous related high precision etched Kapton® products, but it also has strong ties with several research institutions (namely Brookhaven, Yale and MIT) that can help develop and evaluate the performance of the GEM foils produced at Tech-Etch. Additionally, since Tech-Etch is a small company, it also has the capability to produce a large variety of part configurations, as well as the flexibility to shift production methods, equipment, and chemistry to optimize the GEM foil manufacturing process without being constrained by existing work running on high volume continuous coil equipment.
This database is used in the EPA's Superfund Counts Per Minute (CPM) Calculator (https://epa-cpm.ornl.gov/index.html). This database contains conversion factors used in the calculator that help users estimate the expected radiation detector reading, in counts per minute (CPM), corresponding to a measured radioactivity level reported in either pCi/cm² or pCi/g. Because surface contamination and volumetric contamination behave differently, the tool uses separate conversion processes, each based on Monte Carlo N-Particle (MCNP)–derived conversion factors. The CPM Calculator supports conversions for a range of common environmental media—including soil, steel, glass, drywall, concrete, and wood—to generate detector-ready CPM values. The primary goal of this tool is to enable more efficient, real-time field measurements, reducing reliance on laboratory analyses and ultimately saving both time and money during Superfund assessments.
At ports of entry, radiation detectors could be mounted on container gantry crane spreaders to monitor cargo containers entering and leaving the country. These detectors would have to withstand the extreme physical conditions experienced by these spreaders during normal operations. Physical shock data from the gable ends of a spreader were recorded during the loading and unloading of a cargo ship by twohard mounted PCB Piezotronics model 340A50 accelerometers and two Lansmont SAVER 9X30 units(with padding). The majority of large shocks were observed in the vertical direction. The Lansmont units recorded mean shocks of 22.215 ±1.174and 23.776 ±1.140g, while the PCB accelerometers recorded mean shocks of 31.608 ±1.798and 37.072 ±2.015g in this direction. Maximum shocks were as high as 118.854 g. A scatter plot of observed peak acceleration versus velocity change is presented to allow comparison with the damage boundary curve for any planned instrumentation for future systems. Furthermore, it is hoped that the results of this research will aid in the design of future crane-mounted systems.
Gamma radiation detection and measurement with emphasis on space and astronautical applications - abstracts