NuSec Detection Science Workshop 2026

Wednesday 11 Feb 2026, 09:00 → 17:00 Europe/London

National Physical Laboratory

Paul Sellin (University of Surrey)

NuSec Technical Workshop 2026

The NuSec Detection Science Workshop 2026 takes place at National Physical Laboratory on Wednesday 11 February 2026.  This one day in-person meeting is aimed at all researchers working on detection science for nuclear security applications. 

The technical scope of the workshop will cover all detection science topics relevant to NTRnet, with a particular focus on the following areas:

• new detectors for nuclear security applications, including perovskites, new scintillators, and neutron detectors.
• detection systems, instrumentation, and field trials relevant to nuclear security.
• 'Big data' networks and AI/machine learning algorithms, with updates from the recent SIGMA data challenge.

The program will include a mixture of invited talks from senior researchers, and presentations from PhD students and early career researchers. 

To register your attendance at the NuSec workshop please submit your registration details using the Workshop Registration page. There is no charge to register for the NuSec workshop. We regret that we are not able to offer online attendance for this workshop. 

The workshop is run by the NTR-Net doctoral training network, and we will present the latest news and funding opportunities from NTRnet.  

09:00 → 09:30 Registration and Coffee

09:30 → 11:00 Session 1

09:30 Detector development at the University of Surrey

The detection of neutrons with a variety of energies has impact that spans the realms of fundamental and applied physics. At the University of Surrey, we undertake research into both novel detector materials and the application of more established materials for neutron detection, with a focus on scintillator detectors.

A summary of recent work performed by the group will be presented, with a focus on inorganic materials and their response to neutrons, as well as how results can be improved using novel analysis techniques. Research will be presented based on work performed in-house, using the University of Surrey’s radiation laboratories, as well as work done at the National Physical Laboratory’s neutron facility.

Speaker: Jack Henderson (University of Surrey)

09:45 The Development of Hard X-ray Imaging Detectors at STFC

This presentation will give an overview of current work at the STFC Detector Development Group to produce a new generation of X-ray imaging detectors for hard X-rays (5 - 600keV) utilising modern compound semiconductor sensor materials such as HF-CdZnTe for photon science applications.

These developments include HEXITEC-MHz, a new generation of our High Energy X-ray Imaging Technology that now operates at a continuous 1 million frames per second. With 80 x 80 pixels on a 250$\mu$m pitch, this high frame rate now enables the capture of high resolution (FWHM ~ 1keV) per pixel spectroscopy at photon fluxes of up to 10$^{8}$ photons s$^{-1}$ mm$^{2}$. $^{[1]}$ Recent experiments alongside Pacific Northwestern National Laboratory (USA) have used the system to demonstrate different imaging modalities including dynamic spectroscopic imaging of ion drift in a solution under a magnetic field with a 250ms temporal resolution and simultaneous spectroscopic radiography, energy dispersive and angular dispersive X-ray diffraction of powder samples.

An update on on the XIDyn project, a collaborative X-ray detector development between STFC, ESRF, Diamond Lightsource, University of Heidelberg, and EuXFEL, will also be given $^{[2]}$. The full XIDyn ASIC which will be delivered by summer 2026 consists of 144 x 192 pixels on a 110$\mu$m pitch and operates at continuous frame rates of >100kHz. Using a novel charge cancellation and digitisation design, the detector is capable of capturing images at photon fluxes of up to 10$^{12}$ photons s$^{-1}$ mm$^{-2}$. Results from the current test chip will be used to illustrate the capabilities of the technology.

References

[1] M.C. Veale et al 2023 JINST 18 P07048
[2] https://www.technology.stfc.ac.uk/Pages/News-Conferences-and-Publications/Conferences-Visits-and-Events/SRI2024/SRI2024-Presentations.aspx

Speaker: Dr Matthew Veale (UKRI Science & Technology Facilities Council)

10:00 Long-Term High-Voltage Bias Stability and Degradation Pathways in Perovskite Single-Photon Counting Radiation Detectors

Current existing semiconductor radiation detection technologies, such as Cadmium Telluride (CdTe), Cadmium Zinc Telluride (CZT), High-purity Germanium (HpGe) and Silicon (Si), suffer from several limitations. These include high production costs, the need for cryogenic cooling (for HpGe), and insufficient stopping power in materials composed of low-atomic-number elements (such as Si). These challenges have motivated the radiation detection community to investigate novel materials that offer lower production costs, the ability to operate at room temperature, and high stopping power for semiconductor radiation detection technologies.
Perovskite Single Crystals (PSCs) have emerged as a promising candidate for direct radiation detection in photon-counting mode due to their excellent optoelectronic properties, low defect density, and high mobility-lifetime products (µͳ). Despite these advantages, ion migration in PSCs poses a significant obstacle for the stable long-term operation of these devices. Under high electric fields, ion migration accelerates the electrochemical reactions at the metal/perovskite interface, leading to device degradation. This remains a significant barrier to the commercialisation of PSC-based radiation detectors.
In this work, hybrid PSCs (FAPbBr3) are grown from solution using a low-cost, low-temperature method called inverse temperature crystallisation (ITC). These PSCs are polished to achieve smooth, mirror-like surfaces, and metal electrodes, such as Bi and Au, are deposited by thermal evaporation. Both single-pad and guard-ring device architectures are fabricated. These detectors exhibit excellent charge-transport properties, including high hole mobilities of 190 cm^2 V^(-1) s^(-1) and a high hole µͳ of 2.7 x 10 ^(-3) cm^2 V^(-1). Importantly, guard ring devices demonstrate an order of magnitude reduction of dark current – from 29 nA cm^(-2) in single pad detectors to 2.9 nA cm^(-2) in guard ring devices, highlighting the importance of electrode engineering on suppressing the leakage currents of these devices.
Long-term dark current measurements were conducted for both device types, and X-ray photoelectron spectroscopy (XPS) was performed to characterise the chemical composition and bonding environment of the crystal's surface and bulk following extended device biasing. Additionally, the implementation of charge-blocking layers via atomic-layer deposition (ALD) is explored as a strategy to mitigate ion migration toward the anode metal electrode. Finally, long-term single-photon-counting radiation-detection measurements are performed using 241Am 5.49 MeV α-particles, 59.5 keV γ-rays, and 137Cs 662 keV γ-rays to investigate the device's long-term operation under constant radiation exposure.

Speaker: Mr Jayana Jayarathne (University of Surrey)

10:15 Using a HPGe-PIPSBox detector system to compare the noble gases produced by fission from U-235 and Cm-248

Noble gases are chemically unreactive and therefore the easiest fission fragments to extract from fissioned samples. Krypton and xenon isotopes are relatively highly produced making them good candidates for measurement. Sitting in different mass peaks, their ratio can also be used to differentiate between fission sources. Using a beta-gamma system to measure the extracted gases improve signal-to-noise and thus sensitivity to these radiogases. The poster presents data from Cm-248 and U-235 sources.

Speaker: Ms Sifa Poulton (National Physical Laboratory)

10:30 Bismuth-loaded Plastic Scintillator for Nuclear Security Applications

In recent years a great deal of research has been devoted to the development of so-called spectroscopic plastic scintillator. The addition of high-Z materials increases the stopping power and photopeak efficiency of plastic scintillator albeit generally with a reduction in light yield. Common elements used for this development include tin (Z=50) and lead (Z=82), and such metal-loaded plastics are currently available commercially. Here we present characterisation of two new materials developed at Lawrence Livermore National Laboratory which make use of bismuth (Z=83) to enhance the effective atomic number of the scintillator.

Bi-PVT shows promise as a potential drop-in replacement for existing metal-loaded plastic systems. In particular, Bi-PVT is being investigated as a radiation portal monitor upgrade material, and we will present results of its implementation within a commercial dosimeter. Conversely, the novel material BLIP (Bismuth-Loaded Iridium Fluor Plastic) can achieve far higher loadings of metal before light reduction becomes detrimental to the performance of the scintillator. BLIP has been shown to surpass NaI(Tl) in the metric of counts per unit mass, suggesting deployment scenarios where weight becomes a major factor – aerial or backpack-mounted radiation detection equipment.

UK Ministry of Defence © Crown owned copyright 2025/AWE

Speaker: George Dalton

10:45 Clear and Bright X-Ray Imaging with Nanophotonic Scintillators

Lens-based imaging detectors such as those typically used for MeV X-ray imaging and synchrotron-based imaging suffer greatly from poor collection efficiency, typically recording only ~1% of light emitted by the scintillator. However, spatially periodic, sub-wavelength photonic structures provide a means to modify the emission, transport and outcoupling of photons in a crystal. Nanoscale patterns applied to scintillators have been shown to generate significant enhancement in the intensity of the detected signal.
Here, we present investigation of a range of nanophotonic structures made using different technologies, targeting improvements in lens-based imaging detectors. We present a range of results including synchrotron and lab-based measurements of signal enhancement in excess of 300%, as compared to unpatterned scintillators. In contrast to the blurring effects which would be expected when recording images using scintillators with randomly roughened surfaces, we have found that the highly ordered surface nanophotonic patterns do not necessarily produce a drop in spatial resolution, allowing for high-quality X-ray imaging.
In addition, we present the results of synchrotron experiments carried out using a microbeam X-ray and a partially patterned scintillator, including a remote outcoupling experiment which demonstrates how a small-area pattern emits light more readily than the surrounding scintillator even when the pattern itself is not directly illuminated. These experiments have provided greater understanding of the transport and outcoupling of light in these materials, further elucidating the mechanism of scintillation enhancement and guiding further development.

Speaker: Dr Isabel Braddock (Science and Technology Facilities Council)

11:00 → 11:30 Coffee Break

11:30 → 13:00 Session 2

11:30 Rapid Modelling of Novel Nuclear Scenarios for Response Guidance and Training

Within the nuclear security landscape, threats can exist within a variety of challenging environments. Developing the most appropriate procedure for a chaotic scenario can be difficult without having an appropriate model to work with, and uncertainty in the expected activity and shielding of a radioactive source can lead to sub-optimal containment and unnecessarily high irradiation.

Whilst several advancements have been made in the field of nuclear instrumentation to aid in the localisation of radioactive sources, these localisations are typically constrained to surfaces which fail to account for self-shielding effects and provide accurate dose estimates. In order to fully quantify the activity and the accurately estimate dose more intensive modelling is required which comes with significant time requirements.

Within this work we demonstrate the use of a novel frontend interface for the modelling of challenging radioactive environments. NuClearVision provides an intuitive frontend to MCNP, GEANT4 and OpenMC with a unified GUI capable of producing industry standard simulations from scratch with minimal user input in a shortened timeframe. Our software fully handles the geometric initialisation, transforms, variance reduction and material assignments automatically through transcription layers, allowing for the end user to quickly make representative simulations of their scenario for a variety of applications. Support for LIDAR point clouds and CAD models allows for accurate modelling of complex objects, whilst macrobodies are available for approximations. The results of these simulations feed into a full-scale digital twin of the scenario, allowing for complex path planning, dosimetry and training within a virtual reality simulation.

Speaker: Fraser Holloway (The University of Liverpool)

11:45 Remote characterisation of buried and spatially distributed radioactive sources using full-spectrum analysis

Remote identification of buried or spatially distributed radioactive material is difficult because surface measurements mix natural background with any anthropogenic contribution. Activity may lie on the ground surface or be buried beneath sediment, and these geometries impose different attenuation and scattering effects that distort spectra. Burial depth suppresses photopeaks, hardens the spectrum and reduces count rate, making shielded activity appear indistinguishable from genuinely low activity. This distinction matters operationally, as concealed sources or vertically migrating legacy discharges can present signatures similar to benign material unless depth effects are accounted for. Effective remote sensing therefore requires analytical methods able to interpret these spectral modifications, attribute them to source depth or distribution and convert measurements into reliable dose and activity estimates for environmental and emergency-response applications.

This work presents a scenario specific full spectrum analysis (FSA) approach for extracting information on buried or distributed sources from remotely acquired gamma spectra using uncrewed aerial vehicles (UAVs). FSA treats the measured spectrum as a non-negative combination of Monte Carlo generated unit spectra that represent isotopes of interest (U-238, Th-232, K-40, Cs-137 and others) under different physical source geometries that can be modelled to best explain the physical environment. By exploiting the full spectral shape rather than relying solely on photopeaks, FSA captures the influence of scattering, attenuation and depth effects that distort spectra from buried or mixed sources. This enables a more accurate activity estimation and qualitative discrimination between surface bound and subsurface contributions in scenarios where conventional region-of-interest or window-based methods lack the ability to separate overlapping isotopic components.

The methodology is demonstrated using UAV collected gamma spectrometry data across the River Esk estuary at Ravenglass in Cumbria. A salt-marsh environment containing naturally occurring K, U and Th within the sediment alongside well-documented anthropogenic contaminants from historical Sellafield discharges, including Cs-137, Am-241, Sr-90 and plutonium isotopes. Two UAV survey campaigns have been conducted over two years, using first a 37 cm³ CsI detector and later a larger 237 cm³. A Monte-Carlo-based ambient dose equivalent H*(10) pipeline yielded a maximum dose rate across the surveyed marshland of 0.092 µSv h⁻¹. This is in close agreement with recent Sellafield Ltd. and RIFE (Radioactivity in Food and the Environment ) ground-sample studies of the same location, which report a maximum dose of 0.098 µSv h⁻¹. Application of FSA to the same dataset provided spatial activity (Bq) estimates for NORM isotopes and successfully identified Cs-137 in regions consistent with documented deposition patterns. The approach enabled clear spatial discrimination between NORM and Cs-137 and produced isotope-specific activity maps that could be directly compared with the dose distribution. The highest dose regions were geospatially coincident with the areas of greatest Cs-137 activity, while NORM contributions were laterally homogeneous across the wider marsh. This combined interpretation provides surveyors and responders with clearer situational understanding, supporting defensible risk assessment and targeted remediation.

Speaker: Ewan Woodbridge (University of Bristol)

12:00 Single Particle Uranium Analysis by Triple Quadrupole Time of Flight Mass Spectrometry for Nuclear Forensics

The International Atomic Energy Association’s (IAEA) Network of Analytical Labs (NWAL) performs particle analyses from swipe samples for the monitoring of nuclear facilities and the radioactive material with two major focuses: detection of uranium bearing particles, and confirmation of declared enrichment.
Currently this analysis is carried out by large geometry secondary ion mass spectrometry (LG-SIMS) or fission track thermal ion mass spectrometry (FT-TIMS). Analysis using these instruments is both expensive and time consuming. In addition, FT-TIMS requires access to neutrons for irradiation, a site-specific requirement that heavily limits its availability. The number of samples needing analysis by NWAL is increasing rapidly, heavily taxing their resources. A faster analytical method is necessary to keep up with the growing number of samples.
The Penn State REACTR lab has acquired a Nu Vitesse inductively-coupled-plasma time-of-flight mass spectrometer (ICP-TOF-MS) with a triple quadrupole addition. The Nu Vitesse time of flight system has a very fast spectral acquisition speed which allows it to differentiate suspended particles from solution. Combined with an Image Geo 193 laser ablation system, this instrument is capable of performing spatially resolved isotopic and chemical analysis of solid samples. Both functions are of particular interest for testing IAEA swipes, and warrant investigation.
With the fast spectral acquisition capability of the ICP-TOF-MS and the laser ablation capability this system provides two possible approaches to analyzing uranium particles on IAEA swipes. The first approach involves pulling particles off the cotton swipe to create a suspension which can be analyzed directly by the machine. The second approach involves using the laser ablation system to map and ablate individual particles and collect their individual make up with the detector. Both methods provide the ability to measure the individual chemical and isotopic make up of particles, information that is useful for detecting anthropogenic sources of uranium.
The Nu Vitesse system should offer an improvement to speed and cost relative to the current systems used by NWAL. In addition, The time-of-flight mass spectrometer provides the ability to corelate particle composition with uranium isotopic abundance.

Speaker: Michael Romero (Pennsylvania State University)

12:15 Optimizing Lanthanide Accelerator Mass Spectrometry for its use in Nuclear Data Production

Accelerator Mass Spectrometry (AMS) is traditionally applied to radiocarbon dating, and cosmogenic nuclides but has the capability of analyzing lanthanides [1], [2]. Lanthanides prove difficult to measure via AMS due to their inherent contamination with each other and the isobar suppression limits of the system. This study aims to develop a sensitive technique for measuring lanthanides via Accelerator Mass Spectrometry at the SUERC AMS Laboratory. AMS measurements of lanthanide reaction products from neutron and charge particle reactions will provide nuclear data that is of interest to the nuclear data community, that is currently unmeasurable by standard decay spectroscopy [3]. The method development includes ion source characterisation, radiochemistry, accelerator optimization and detector development for the rare earth elements (REE).

The initial exploration determined baseline low energy mass scans for all REE in oxide form. The optimal starting material was determined by collecting mass scans of varying REE starting samples. The counterions (oxide, fluoride), mixtures of calcium fluoride, metal binders (niobium, silver) and cathode material (aluminum and copper) were altered to determine the effect on the current output. The general trend showed that samples performed better when in an oxide:niobium, 1:2 ratio in an aluminum cathode. All data is applied to a machine learning algorithm that predicts ion current, starting sample and ranks feature importance for the model.

The 5 MV tandem accelerator was used to explore high energy mass scans of the top five performing REE from the low energy system. This provided insight on the length of irradiation needed, ion efficiency, and the purity required to get a well resolved ratio of reaction products and therefore relative cross section measurement at the final detector. High energy data will be used alongside gas stopping simulations to determine the expected energy deposits in the final detector along with any changes that need to be made to the detector.

[1] L. K. Fifield, “Accelerator mass spectrometry and its applications,” Reports on Progress in Physics, vol. 62, p. 1223, Aug 1999.
[2] R. Middleton, A Negative-Ion Cookbook. Department of Physics, University of Pennsylvania, 1989.
[3] T. Wright, S. Bennett, S. Heinitz, U. Koester, R. Mills, T. Soldner, P. Steier, A. Wallner, and T. Wieninger, “Measurement of the 13c(n,γ) thermal cross section via neutron irradiation and AMS,” The European Physical Journal A, vol. 55, 11 2019

Speaker: Victoria Johnson (University of Glasgow/SUERC)

13:00 → 14:00 Lunch and Posters

14:00 → 15:30 Session 3

14:00 Community insights on establishing a centre for AI in applied nuclear physics

In October 2025 a one-day community workshop was convened to explore the vision, scope, and feasibility of establishing a Centre for AI in Applied Nuclear Physics, with relevance to both civil and defence domains. The event brought together researchers, industry partners, and government stakeholders for a series of interactive sessions, keynote presentations, and a community poster forum.

This submission will report the key findings and themes that emerged from the workshop. These include community priorities for shared infrastructure, opportunities for coordinated development of open datasets, and identified needs in education and career pathways. Consensus views will be summarised alongside noted areas of divergence, and practical considerations raised regarding the Centre’s proposed structure, remit, and long-term sustainability. This feedback aims to ensure transparency, maintain momentum, and invite further input from the nuclear community.

Speaker: Caroline Shenton-Taylor (University of Surrey)

14:30 Innovation in neutron and gamma sensor technology and AI-enhanced analysis for security applications

Global geo-political and economic instabilities and uncertainties mean that our security services are under increasing pressure to respond to suspected and genuine incidents under time pressures and with limited resources. These conditions impose challenges on the equipment used and the underpinning technologies, in order to ensure ease of use, robustness under increasingly under environmental conditions, detection sensitivity and technical reliability with respect to false alarms, detection reliability and cost-effectiveness.
Mirion serves many customers in the security and nuclear material safeguards services, supplying products in many countries, and in support of many facets of the industries. This includes working extensively with users, regulators, and laboratories engaged in the accreditation of the technology and products. It also requires careful maintenance of the underlying technology portfolio.
Key technologies underpinning security applications are usually based on remote detection of characteristic radiation signatures. This ensures ease of access for operators while minimising direct exposure to potentially hazardous items. Normally, this means that gamma spectroscopy or gross gamma counting (dose rate), or neutron measurements (either dose rate or neutron counting in Totals or Coincidence modes) are suitable for use with inspection probes. In order to deal with varied requirements for deployment, delivery of these detectors through either Unattended Automated Vehicles (UAVs), backpacks, crawlers, or quadruped robots or similar, are often considered.
In Mirion, our teams work extensively with customers to conduct field trials, ensuring user interfaces, ergonomics, detector responsiveness and serviceability, are all matched to user requirements. As part of our technology program, we work with many national laboratories and universities to ensure that maximum advantage is taken of existing technology, thus minimising development time and costs to convert into field products, whilst actively supporting and developing skills development through the universities through for example PhD programs. In this paper we present examples of such work with reference to previous case studies. Examples include exploration into emerging detector technologies such as perovskites, diamond detectors and Si carbides, and aligning technological features and performance characteristics, for example relative neutron and gamma sensitivity, to the application - driven field conditions, for example with respect to temperature and radiation hardness of components. Our work also includes constant appraisal of neutron detection technology and we give examples of lessons learned from field-proven installations involving neutron detectors operating in harsh environmental conditions for example waste management, and where this experience can carry over to in-field applications such as safeguards, security and emergency response inspections.
We give an industry perspective on the issues surrounding data management, from experience serving many fields. We describe how software integration tools can streamline data collection and make it more universally accessible to different customer teams. Increasingly, Artificial Intelligence techniques are becoming studied more widely. Again we give an industry perspective with reference to our developments aimed at accelerating and automating spectral analysis in ways that allow complex patterns of characteristic features to be recognised, whilst addressing issues of user confidence and validation.

Speaker: Patrick Chard (Mirion Technologies (Canberra UK) Ltd)

14:45 Evaluating Object Detection Neural Networks for Landmine Detection: Training and Performance Analysis with Synthetic and Real-World Data

Reliable UXO detection remains one of the most persistent sensing challenges due to the diversity of threats and the variability of real-world environments. This study explores the use of synthetic data to train object detection models for landmine detection. The YOLOV8n model trained on n=1000 real images achieved a mAP@50 of 0.983, a precision of 0.966 and a recall of 0.961. The best synthetic model, starting from YOLOv8n, used n=10,000 images with a 90:10 UE:CPL split, yielding a mAP@50 score of 0.936, a precision of 0.912, and a recall of 0.880. These findings indicate that comparable model performance can be achieved with entirely synthetic data, with a greatly reduced lead time due to automated data generation and bounding box labelling. Varying setup conditions for CPL models also found that matching the pixel size in training images to that of the final data yielded the most robust models. These experiments further demonstrated that earlier CPL research, showing that patch-level realism alone was sufficient in low-noise environments, remains valid even when extended to more cluttered and stochastic background conditions.

Speaker: Mr Seb Pereira (University of Bristol)

15:30 → 16:30 Session 4 - Discussion

15:30 Closing Remarks

Speaker: Thomas Scott (University of Bristol)