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MODULAR DETECTION SYSTEM FOR SPECIAL NUCLEAR MATERIAL

Final Report Summary - MODES_SNM (MODULAR DETECTION SYSTEM FOR SPECIAL NUCLEAR MATERIAL)

Executive Summary:
Special Nuclear Materials (SNM), Highly Enriched Uranium and Plutonium, are difficult to detect, especially when masked or shielded. To increase the detection capability, gamma rays and neutrons emitted by SNM have to be counted separately in order to increase the sensitivity against natural background that is mainly constituted by gamma-rays. In the MODES_SNM project, the objective of detecting such materials is pursued by optimizing a novel technology recently developed by ARKTIS based on specialized high-pressure gas scintillators. The developed set of specialized scintillators together with novel digital front-end electronics and software tools allow the detection of all relevant radiation types and to engineer a prototype of a modular, mobile detection system that has been qualified under laboratory conditions. Moreover, a van-mounted system was prepared and tested in an on-field campaign driven by the end-user group established in the project. The on-field campaign was focused on both performance and usability aspects including the verification of the man-machine interface. The MODES_SNM system fits with the IAEA requirements for Portable Radiation Scanners (PRS). It shall satisfy two major requirements:
1) improving the state of art in detection of radioactive and Special Nuclear Material in terms of sensitivity for shielded SNM and capability of identifying the neutron source;
2) being directly usable by emergency responders in the field filling the gap between Radiation Portal Monitors and hand-held devices.

Starting from the pre existing know-how of ARKTIS in the field of high pressure noble gas (4He) scintillation detectors, the MODES_SNM project aimed first at a general optimization of the detector with the goal of designing and realizing the modular mobile system described below:
1) Optimization of the mechanical design of the high-pressure 4He gas cells for fast neutrons to minimize weight. Using ARKTIS technology, new types of detectors have been developed using noble gas cells: a gamma ray sensor using Xe gas and a thermal neutron sensor by using the 4He technology but equipped with a suitable slow neutron converter. In this way a suite of detectors capable of gamma ray, fast and thermal neutron detection, and perform spectroscopy, all based on the same technology and using the same electronics front-end and DAQ. It is important to stress that each type of detector (4He, Xe and 4He with converter) is specialized to provide information of different types of radiation: the fast neutron emitted directly from SNM or other neutron sources, the gamma-ray that bring fingerprints of the emitter, the thermal neutrons that result from shielded neutron sources. Moreover studies and development geared towards the replacement of the photomultipliers in future systems with solid-state devices to reduce the size and increase robustness.
2) Design of compact, low power front-end electronics based on CAEN know-how on Digital Pulse Processing and HV power supplies. Front-end electronics is battery operated allowing several hours continuous operation in field conditions.
3) A suitable INFORMATION SYSTEM (IS) has been prepared. The IS manages and controls the detectors, including start-up operations and calibrations. It manages and analyzes the data flow from the detectors to achieve on line: 1) the rate of all radiation species compared with the background level providing separated visual and audio alarms for gamma-rays, fast neutron and thermal neutrons; 2) in case of alarm, the operator performs longer measurements to validate the alarms and identify the radiation sources; 3) the analysis of gamma ray spectra is performed for isotope identification; 4) data fusion of all detectors and presentation of the resulting identification of neutron sources with indication of the presence of shielding.
This MODES_SNM prototype represents the final deliverable of the project. It is modular and scalable, divided into so-called system blocks easily mounted and removed into/onto vehicles:
Block A consists of all system electronics including power supply and battery, signal processing electronics and computing. Batteries are placed outside the Block A. Blocks B consists of arrays of detectors, selected from the suite of gamma, fast and thermal neutron. The current prototype consists of seven Blocks B: four with fast neutron detectors, one with thermal neutron detectors and two with gamma ray detectors. Detectors have been validated both in laboratory conditions and during the demonstration campaign. Finally, the prototype has been integrated in a van-mounted solution that was used for the field demonstration in two major European seaports (Rotterdam and Dublin), the Heathrow airport and custom gates in Switzerland. The prototype was operated successfully by end-user without showing important hardware/software problems. During the field demonstration the total tour was approximately 6000 km. Furthermore, a software up-grade was performed to satisfy some end-user suggestions.

The final results of the project is a system with:
Improved SNM detection performance to detect weak or well-shielded SNM or SNM at larger stand-off. The proposed technology incorporates thermal and fast neutron detectors along with gamma ray detectors. These measurements are complementary: their combined power provides the novel capability of identifying the neutron source.
Improved usability: the MODES_SNM system offers single operator GUI (rapid primary screening and threat identification), being rapidly re-locatable or usable directly as a vehicle-mounted system, enhancing the portability, and allowing adaptability to varying threat situations.
The end-user evaluation of the system prototype is largely positive with detailed indications of possible improvements in view of a future second generation commercial system. Consequently all project goals have been achieved.


Project Context and Objectives:
The MODES_SNM project was planned over a period of 30 months. The first part, up to month M20 (M1-M15) was devoted to the initial R&D phase in which the MODES_SNM prototype components (hardware and software) were designed, constructed, tested and produced. The R&D work was guided by the preliminary study of the end-user requirements (WP1) that set the general constrains in order to obtain a substantial improvement of the currently available commercial instrumentation within the expectations from the end user that will operate in future such novel system. The staring points of the MODES_SNM project were the ARKTIS detector technology, the digital read-out electronics from CAEN and the know-how of the universities and research center in the MODES_SNM collaboration that contributed to improve hardware and develop software tools for the optimal usage of the detectors. In details the project objectives can be summarized in the following points:
1) Optimization with respect of weight and size of the currently available ARKTIS high pressure 4He tubes used to detect fast neutrons (WP2-T2.1).
2) Replacement of the traditional photomultipliers with silicon photomultipliers (WP2-T2.2).
3) Design of a novel high pressure Xe detector to detect gamma rays (WP2-T2.6)
4) Design of a novel high pressure detector with suitable converter to detect low energy neutrons (WP2-T2.7).
5) Start the production and tests of the detectors to be integrated in the MODES_SNM demonstrator (WP2-T2.3; WP2-T2.4)
6) Design and realize a novel power supply for the high pressure tubes (WP2-T2.5)
7) Design and realize the front-end electronics for the high pressure tubes based on digital technology (WP3)
8) Design and realize the software components needed to control the hardware system (detectors and front-end electronics), acquire and analyze the data and provide suitable information to the operator (WP4)
9) Design and realize an user-friendly Man-Machine interface based on the end-user requirements (WP4)

The hardware/software sub-components developed under WP2, WP3 and WP4 were the input for the system integration performed in WP5. The fully integrated MODES_SNM prototype was then characterized under laboratory conditions in WP6 to verify that the detector blocks meet the expected performances. At the end of WP6 the system was ready to be used in the demonstration activity (WP7) as end-user driven field tests. This activity was prepared with two different actions:
a) Establishing a group of interested end-user that are available to perform the field-tests.
b) Preparing a training course to present the MODES_SNM system to the end-user and provide possibility of learning how to operate it.
c) Running field tests in few European locations with the end-user directly operating the system.
The end-users provided feed-back to the MODES_SNM collaboration regarding the system performance as well as the possibility of further development.
Finally it has to be mentioned that during the field tests the system was used essentially in the detection/identification of NORMs (i.e. Naturally Occurring Radioactive Material) with some tests using radioactive sources. To verify the capability of the system to detect and identify Special Nuclear Material, specific tests were performed at JRC Ispra.

Project Results:
WP1 - Requirements
WP1 aims at analyzing the needs in terms of detection of radioactive and nuclear materials stated by international agencies (IAEA), the European Union and national government as well as the existing IEC and ANSI standards and to translate them into requirements in term of limits of detection, type of system to be realized (human portable, rapidly re-locatable) associated functional requirements and end user requirements for system hardware functionalities and the man-machine interface. The WP1 was scheduled from M=1 to M=3.
T1.1 – Definition of the limits of detection – Completed
Definition of the limits of detection for neutron and gamma-rays as required IAEA. The list of sources to be used in laboratory tests for the prototype has been also defined. The results have been included in D1.1 Requirement Report.

T1.2 - Definition of the technical specifications – Completed
Definition of technical specifications based on the current design of ARKTIS neutron and gamma-ray detector. The number of needed detectors has been defined in case of different applications including van mounted or fixed installations of the MODES-SNM prototype and the relative scanning speed. Numerical simulations were developed to provide reliable figures.

T1.3 – Definition of the end-user requirements – Completed
By using the IAEA specification for Portable Radiation Scanner (PRS), the end-user requirements have been translated in term of technical specifications for hardware and software for the different use of the MODES-SNM prototype.

T1.4 – Report writing – Completed
The final deliverable D1.1 Requirement report was prepared and delivered on time at the end of M3. Moreover, this report was analyzed by the project Advisory Board in its first meeting. A revised version of the D1.1 report was than prepared taking into account the AB suggestions.
WP1 Highlights: the work package was successfully completed on time. The time sequence of the task as defined in Annex 1 was slightly modified due to strong connection between limits, technical specs and requirements in the different possible use cases of the MODES-SNM prototype. In any case the Deliverable 1.1 was prepared in due time. Consequently the Milestone MS1: Requirements (Report available) was fulfilled. A second revised version of the D1.1 was prepared after the recommendation from the project Advisory Board.
WP1 Deviations: WP1 shows no deviation with respect to the project plan.


WP2 - Detector prototype optimization and production
The focus of WP2 was to perform research and development (R&D) of the detector prototypes. Further steps included their production, lab characterization, and quality assurance.
The final MODES_SNM detection system is designed to detect both thermal and fast neutrons as well as gamma rays. While the R&D work on the fast neutron detector concentrated on optimization of the existing ARKTIS high pressure cell in terms of weight reduction and certification, new developments to use noble gas scintillation for thermal neutron and gamma ray detection (starting from the original ARKTIS high pressure cell) were sought after. In this work package, also R&D studies of silicon photomultipliers as viable replacement of standard photomultiplier tubes (PMTs) were performed. Replacing PMTs with SiPMs could significantly improve the compactness and deliver very rugged detectors in future prototypes.

WP2 was scheduled from M=4 to M=20. All milestones could be reached and deliverables submitted, with delays of max. 2 months.
Achieved milestones within WP2 are: MS2: "High pressure tubes", MS3: "SiPM applicability", MS4: "Xe detector for Gamma", MS5: "Thermal neutron detector", MS6: "Quality control". For all milestones in WP2, the scheduled outcome was "performance accomplishment".
The submitted deliverables are: D2.1 "Design of optimized detector", M6; D2.2 "Detector prototype", M10; D2.3 "Power supply prototype", M13. D2.4 "Preliminary lab characterization and quality control", M14. Deliverable D2.5 "Detector demonstrator prototypes" was scheduled for M20. All of the deliverables in WP2 have dissemination level CO.
A description of each task and its results is listed in the following:

T2.1 – Weight and size optimization of the design of high pressure scintillation tubes – Completed
Based on the report D1.1 ETH, in collaboration with ARKTIS, has reworked the existing detector design, producing an optimization in size and weight, with the goal of enhancing the portability.
In particular, for the fast neutron detector, taking the existing ARKTIS detector as a starting point, an improved technical design has been produced, with reduced weight and size. Part of the weight gains are due to the replacement of all PMT metal protection cylinders with custom-made ones utilizing carbon fiber with a thin metal deposition, developed and delivered by UNILIV.
For the thermal neutron detector, being a completely new detector, only a conceptual design was proposed. For the high pressure xenon gamma ray detector, where a basic prototype existed, a new conceptual design was produced, optimized mainly for sensitivity to gamma rays, for the use of high pressure xenon rather than helium, and increased light yield.
The possibility to replace the PMT based readout with a SiPM readout was also considered.
The report D2.1 "Preliminary design of optimized detector" was delivered within the M6 deadline.

T2.2 - Adaption for use of SiPM for the scintillation light readout– Completed
Conventional photomultipliers are widely deployed with today's scintillation detectors, mainly because of their favorable combination of high gain, low noise, fast response, and large area of collection. Alternatives to conventional photomultipliers are solid state semiconductor devices, such as Silicon Photo-Multipliers (SiPM hence-over). SiPM represent the state of the art for visible light detection with single photon sensitivity and photon number resolving capability. Compactness, robustness, low cost, low operating voltage and power consumption represent the numerous advantages over traditional photo-detectors. The main drawbacks in the SiPM technology possibly limiting their straightforward application as a replacement of photo-multiplier tubes are essentially connected to the active area size, currently limited to dies of 12x12 mm2 and dark count rates at the level of [0.3 – 1] MHz/mm2.
In order to evaluate the possibility to use SiPM in the detectors based on the ARKTIS technology, the characterization of SiPM arrays produced by HAMAMATSU was undertaken. The full analysis, reported in the MS3 document and in the report at the January 2013 collaboration plenary meeting, was based on the response of the arrays to a calibrated light source and to the scintillation light produced by gamma rays in a LYSO crystal. The main figures of merit were the minimum detectable light and the lowest detectable event rate. Results confirmed the capability of detecting pulses as low as 60 photons, for an interaction rate as low as 100 Hz required to have a detected event rate 5σ away from the noise level. Merging these experimental figures with the expectations by a simulation performed by ARKTIS, the collaboration decided to continue the development of a prototype based on SiPM. However, due to the relatively tight time schedule available to complete the production of the detectors for the MODES_SNM demonstrator system, it was decided to use conventional PMTs in the demonstrator setup. The milestone MS3 "SiPM applicability" was achieved in M8 (scheduled M6).

T2.3 – Prototype Production - Completed
Based on the design report D2.1 ARKTIS manufactured prototypes of fast and thermal neutron and gamma ray detectors and made sure a sufficient number of detectors were ready for subsequent lab tests in T2.4. ARKTIS also developed dedicated electronics for monitoring the pressure and the temperature of the high pressure detectors, which is needed for the slow control system (integrated into the information system in WP4). Due to the tight schedule, only the prototype of the HPHe detector was presented in the report D2.2 " Detector prototype".
Also in this task, SiPM activities went further. The design of a dedicated detector read out by SiPMs was undertaken by ARKTIS, ETH and UINS, embedding 2 arrays of SiPM. ARKTIS and ETH designed customized flanges and kapton bridges to route the sensor signals off the tube. High pressure tests were preliminary undertaken to qualify the prototype. UINS focused on the lab qualification of the arrays delivered by HAMAMATSU, on the optimization of the front-end by signal filtering, shielding and grounding and on the use of standard CAEN off-the-shelf components to be used for the amplification and read-out of the signals. A novel trigger scheme based on a delayed coincidence was also studied.

T2.4 – Lab testing and quality control of prototypes – Completed

Task 2.4 of WP2 focused on the characterization of the prototypes developed during the first year of work: the fast neutron detector, thermal neutron detector, and gamma radiation detector, all based on noble gas scintillation technology and PMTs. Lab characterizations of the thermal and fast neutron detector were performed at the accredited PSI Calibration Laboratory in Villigen, Switzerland, which provides strong and calibrated gamma and neutron fields. Tests of the gamma ray detector were performed both at NCBJ in Poland and at ARKTIS and ETH labs. The quality control showed that the required performance stated in D1.1 can be met. The quality performance requirement was thus successfully met. During the prototyping, pressure tests have been performed at the Paul Scherrer Institute in Villigen, Switzerland. Certified pressure test were performed at TÜV Süd.
The results are summarized in D2.4 "Preliminary lab characterization and quality control" and the report for MS6 " Quality performances accomplishment". Due to delays in the delivery of parts of the Xenon detector, the full characterization of the detectors was reported in M15 instead of M14.
Prototype testing of the SiPM detector solution went on in parallel. Tests of the customized, prototype tube embedding 2 SiPM arrays was performed with high pressure 4He and Xenon, addressing the key issues of counting sensitivity, gamma-neutron separation (for He) and gamma spectrum reconstruction (for Xenon). Tests were initially performed in M13 at the ARKTIS premises with a 252Cf (37kBq activity) and a 60Co source (40kBq activity) in contact with the tube. Real-time and off-line analysis proved the validity of the proposed concept, with a neutron efficiency and a gamma rejection level comparable to the standard, PMT-based solution. At the same time, it was clear that engineering a full scale prototype based on SiPM would have not respected the project schedule and would have implied a high risk profile. As a consequence, the consortium decided:
a. To base the production of the full scale prototype on the PMT based detector
b. To continue the R&D activities on the SiPM based solution, at constant budget and limiting the variation with respect to the original workplan to the WP2 duration and to a shift between the cost categories from consumables to manpower.
The proposal was presented to the Project Officer during the Mid-Term meeting and approved.

Since the Mid-Term, activities in WP2 have continued with the following actions:
1. Second qualification at the ARKTIS premises (June 2013), including the implementation of a real-time, cost-effective advanced triggering scheme and the development of a multi-variate off-line analyses (completed in October 2013).
2. Design, production, commissioning and qualification of a dedicated front-end electronics (completed in December 2013)
3. Comparative evaluation of the SiPM based and the PMT based detector at the Padova-Legnaro labs (January and February 2014)
4. Data analysis and final report to the collaboration during the Dublin meeting (May 2014).
The series of tests confirmed the first results, with SiPM based detectors featuring efficiency & discrimination levels in line with the PMT ones and offering the possibility to:
- Improve the response homogeneity in a full size detector
- Implement a cost effective triggering scheme not requiring the waveform digitization.

T2.5 – Design of the power supply – Completed
The objective of the task was to propose a power supply for the photo-detectors (PMT or SiPM) for the demonstrator system. Following the results of tasks T2.1 and T2.2 where the detectors have been re-designed to optimize the performances in order to fit the MODES_SNM requirements and where the study for the use of SiPM for scintillation light read-out has been done, the proper photo-detectors (PMTs) have been chosen for all the three different kind of radiation detectors. CAEN decided to design a boxed 4-channels power supply with fixed polarities, designed to adapt different HV channels on the same motherboard. The design was completed on time and then it entered in the project flow foreseen for the Front-end electronic system (WP3). The person-months used and the total cost of the activity are very near to the budgeted one. The results were summarized in D2.3 "Power supply prototype". There were no deviations with respect to the project plan.
UINS analyzed the specific requests for SiPM, actually quite different with respect to PMT in terms of maximum voltage (lower by one order of magnitude), control and stability at the 10 mV level and requirement to handle a feedback signal from a temperature sensor, together with the capability to equalize each of the 16 channels in a SiPM matrix. The analysis lead to the design, construction and qualification of a novel biasing and amplification unit showing a significant improvement in terms of minimum detectable light with respect to the off-the-shelf board made available by HAMAMATSU Photonics. Moreover, the board overcame the pick-up problems affecting the performances at low signal rate.

T2.6 – Characterization and lab testing of gamma detection properties (high pressure Xe) – Completed
The high pressure Xenon detector was tested and characterized by ARKTIS, ETH and NCBJ. Preliminary characterization of the Xenon detector was reported in MS4 "Xe detector for Gamma". The performance was compared to state of the art COTS NaI(Tl) detectors. The very encouraging results achieved during the first evaluation phase motivated the choice to extend Task 2.6 in order to allow a redesign of an optimized detector. The characterization of the optimized detector was performed in WP2.4. T2.6 was extended by 2 months to allow for more detailed studies in this relevant phase. The Go-/No-go decision for T2.6 resulted in a clear "Go".

T2.7 – Modification and lab testing of high-pressure scintillation modules for thermal neutron – Completed
The goal of T2.7 was to modify existing ARKTIS scintillation detectors to allow thermal neutron detection by means of inclusion of a neutron capturing material such as Gd, Li or Boron. After the definition of the Requirement Report (D1.1) it was clear that the requirement of detecting neutrons in an high gamma ray background (this is required to detect sources masked by using “commercial” gamma ray sources) rules out the possibility of using the Gd converter since in this case the interaction of neutrons produces gamma rays (and electrons) that can not be separate by the “masking” radiation. At the same time the use of Xenon as counting gas is not convenient because it is very sensitive to the “masking” gamma rays. Consequently the work has been oriented towards the possibility of implementing 6Li-based converters for the detection of thermal neutrons. Two clear advantages can be identified in 6Li: i) the high cross-section for the absorption of thermal neutrons- ii) the products of the absorption reaction are high energetic alpha particles which can be easily detected in pressurized noble gas detector. The work in T2.7 resulted thus in a thermal neutron detector prototype based on the inclusion of 6Li as neutron capturing material.
The Milestone MS5 " Thermal neutron detector" was delayed by 2 months in order to conclude the task with a go / no go decision, to either commit to developing a proprietary thermal neutron detector or else, to recommend and integrate a COTS thermal neutron detector for the MODES_SNM system. The preliminary results achieved during Task 2.7 have been positive and competitive to state-of-the art, resulting in a "Go"-decision.

T2.8 – Design and production of the final layout of the detection modules - Completed
The design of the detectors for the demonstrator were finalized. Tools to get a sustainable and reproducible detector performance in place had to be developed, especially with respect to the coating of the thermal neutron detectors and the Xenon detectors. 8 fast neutron detectors, 2 thermal neutron detectors and 2 Xenon detectors were produced. Stress tests and temperature tests of the detectors were performed. A certification of the detectors was also obtained, to ensure safe travelling and handling. A factory acceptance report assessing the quality was issue. Due to delivery time issues, only one Xenon detector and one thermal neutron detector were shipped to Liverpool for the integration and the remaining identical two were shipped directly to Warsaw where they were integrated. Deliverable D2.5 was therefore completed with 2 months delay. As this delay was foreseeable, it was made sure that at least one example of each detector type was available for integration in Liverpool within the required and scheduled delivery time.

WP2 Highlights: the work package was producing high quality results. The demonstrator system could therefore be equipped with not only fast neutron detectors based on noble gas scintillation, but also thermal neutron and gamma ray detectors based on noble gas scintillation. M16-M20 focused on the final layout, production and lab characterization of the detection modules for the demonstration system. Preliminary results on the Xe gamma ray detector have been published (F.Resnati et al., Suitability of high-pressure xenon as scintillator for gamma ray spectroscopy. Nuclear Instruments and Methods in Physics Research A715 (2013 )87–91) and were also presented at conferences (see WP9). In particular, presentation at the 2013 IEEE NSS-MIC conference: 1. U. Gendotti et al, Development of a High Pressure Xe Gas Scintillator Gamma Rays Spectrometer Based on Primary Light Scintillation, 2. L. Swiderski et al, Non-proportionality and Energy Resolution of Xe Gas Scintillator in Gamma Spectrometry. A final paper is still in preparation, to be published in NIM A. Results on the use of SiPM have been presented at the last ANIMMA Conference (http://animma.com/) and during a seminar at MIT.

WP2 Deviations: WP2 showed no major deviation with respect to the project plan. T2.2 T2.4 T2.6 T2.7 and T2.8 had to be extended minimally (max. 2 months). All milestones and deliverables could be delivered with a max. of 2 months delay.

WP3 – Electronic Front-End design and production
Objectives of the Work Package: To design and produce the electronic front-end, including the data acquisition system for the modular detection system using high-pressure scintillation cells.

T3.1 – Conceptual design of the electronic front-end (M4-M6) – COMPLETED
Objectives: CAEN, together with ARKTIS and UINS, choose the more suited technology (type of digitizer, type of digital filtering) to perform the read out of the SiPM detector matrix and for PMTs.
Results achieved: The analysis has been carried out by CAEN with the contribution of ARKTIS (for the know-how related to the scintillation detectors developed in by them in MODES_SNM) and UINS (for the know-how on SiPM read-out issues and front-end electronics requirements of SiPM devices). The main result of this task is the decision to start a completely new design of a boxed digital acquisition module with higher performances respect to the state-of-the-art CAEN products. This new module will also give the possibility of a new firmware for on-line digital pulse processing to dramatically decrease the data throughput and to simplify the computing hardware of the IS. The conceptual architecture of the front-end electronic system for MODES_SNM has been completely defined.
Deviations: No deviation with respect to the project plan.
Deliverables and Milestones: D3.1 – Front-end System Design (together with T3.2) – DELIVERED ON TIME

T3.2 – Design of the electronic front-end system including DAQ (M7-M12) - COMPLETED
Objectives: Design involves mainly the firmware in the digitizer module that will be chosen, but likely even some characterization of the hardware implementation. UINS and CAEN have a previous agreement to develop read out applications based on SiPM, so the design will be carried out together. This design flows in a technical report (D3.1).
Results achieved: The hardware design of the MODES_SNM boxed read-out module (DT5730 digitizer) has been completed. The firmware design has been completed in draft version, and it will be debugged, tested and finalized once the production of the modules will be completed (as foreseen by task T3.4 starting at M19).
Deviations: In the Annex I was planned to use an existing CAEN digitizer module and to customize it with a proper custom firmware. Following the requirements of the MODES_SNM system, we decided to develop also a new hardware platform in order to accomplish the best read-out performances. Luckily, this additional work has not increased the cost of the task since the cost of resources used is lower than the average cost used for budgeting purpose.
Deliverables and Milestone: D3.1 – Front-end System Design (together with T3.2) – DELIVERED ON TIME

T3.3 – Production of the electronic front-end (M13-M18)- COMPLETED
Objectives: This task includes the realization of the PCB and the complete mounting of all the equipment needed to carry out the data acquisition from the detector.
Results achieved: CAEN completed the production of all the MODES_SNM front-end electronics devices,3 boxed MODES_SNM read-out devices (codename DT5730), 3 boxed MODES_SNM HV power-supply devices (codename DT5533x), 1 optical link board (codename A3818) and of 2 MODES_SNM battery systems. The firmware of the read-out devices was then optimized on the final devices in order to achieve the required performances.
Deviations: No deviation with respect to the project plan.
Deliverables and Milestones:
- D3.2 – Front-end System Prototype (together with T3.4) – DELIVERED ON TIME

T3.4 – Quality control and delivery of the electronic front-end (M19-M20) – COMPLETED
Objectives: All the devices will be tested by CAEN and UINS so to be qualified before being shipped to the integration facilities.
Results achieved: All the devices have been tested with detector emulators. During this quality control, some bug-fixing activities were carried out. The delivery of the devices for the integration phase was done on time.
Deviations: No deviation respect to the project plan.
Deliverables and Milestones:
- D3.2 – Front-end System Prototype (together with T3.3) – DELIVERED ON TIME
- MS8 – Read-out electronics – Performances accomplishment – ACCOMPLISHED
WP3 Highlights: The work package activities were completed as planned, and the results achieved fulfilled the requirements of the system and the project expectations. Several bug-fixing and fine-tuning activities have been done during WP3 to maximize the performances of the electronic section of the system. The electronic front-end of MODES_SNM is an example of a high technology, high density, low power-consumption electronics, characteristics which permitted an easy integration and the ruggedness required for a mobile system. The DT5730 was used in a comparative work of different digitizers to determine the best combination between resolution and sampling frequency. This work was published on Nuclear Instrument and Methods (D. Cester et al, N.I.M. A 748 (2014) 33).
WP3 Deviations: no deviations from the project plan

WP4 – Information System
Objectives of the Work Package: To design and realize the Information System (IS) of the prototype that includes:
1) the control of the detection modules HV system
2) the control of the front-end and DAQ system
3) the setting up system, including automatic calibration procedure
4) the decision tree with the data fusion between different detectors
5) the man-machine interface
The expected results from this WP is the IS ready to be integrated in the Modular System Prototype in WP5.

The Task structure of WP4 can be divided into 3 main periods:
I) M1-M3:
- Task 4.1 – Conceptual Design of the IS
II) M4-M15:
- Task 4.2 – Man Machine Interface
- Task 4.3 – Setting-up and Calibration of the System
- Task 4.4 – Decision Tree
- Task 4.5 – Control System for the Front-End and DAQ
III) M16-M20:
- Task 4.6 – Integration of the IS components
The status report of the different tasks will follow this time structure.

T4.1 – Conceptual Design of the IS (M1-M3) - COMPLETED
Objectives: UNIPD, together with ARKTIS, CAEN and RC, defined the IS specifications. The system is structured in four main software modules: (1) Control system for the HV, electronic front-end and data acquisition; (2) Man-Machine interface (3) decision-making algorithms (decision tree) and (4) Setting-up and automated calibration system.
Results achieved: The analysis has been carried out by UNIPD with the contribution of ARKTIS and CAEN which, as lead participants of WP2 and WP3, have brought the needs from the detectors and front-end electronics point of view, and with RC as representative of the end-user point of view. The main result of this task was the production of Deliverable D4.1 (Information System Conceptual Design) where all main features and strategies of the IS, both from the software and the hardware point of view, have been defined or outlined. Deviations: No deviation respect to the project plan.
Deliverables and Milestones:
- D4.1 – Information System Conceptual Design – DELIVERED ON TIME

T4.2 – Man Machine Interface (M4-M15) - COMPLETED
Objectives: the implementation of the Man-Machine Interface (MMI) is the object of this task. Two different interfaces have been developed: the user interface (easy mode) and the expert one (expert mode). The user interface contains only the basic commands (start, stop and calibration of the system) and a very simple display that generates an alarm signal showing the radiation levels for fast and thermal neutrons and gamma rays and a display with indication of the probable type of radiation source. The expert interface allows the operator to set working parameters of the different system components (HV, FE, analysis software) and access the database containing all information about the hardware, as well as the original data acquired by the system.
Results achieved: The MMI software has been realized according with the specifications using a simple web-based technology, that allows different commonly used devices (like laptops, tablets or smartphones) to be used as client device to remotely access and control the MODES_SNM prototype. All main functionalities have been implemented and finalized as soon as the final versions of the hardware parts (detectors, digitizers, slow controls) were delivered. Most of them have been previously tested using the available hardware. Firmware and red-out software development for the pressure and temperature monitoring electronics delivered in WP2.4 was carried out by ARKTIS. Special attention was set on stability and calibration issues.
Deviations: No deviation respect to the project plan.

T4.3 – Setting-up and calibration of the system (M4-M15) - COMPLETED
Objectives: A specific automatic system is taking care of the setting-up of the system, controlling the physical status (pressure and temperature) of the detectors and initializing the HV and FE system. Moreover, since part of the information is related to the energy released in the detectors, the system is calibrated by using a known weak radiation sources. The stability of the system is monitored during the use by analyzing properly the spectrum due to the natural background.
Results achieved: The Setting-up and Calibration Control System (SU&CCS) software has been realized in accordance with the specifications. All main functionalities have been implemented and finalized as soon as the final versions of the slow control boards were delivered. Most of them have been tested previously using the available hardware.
Deviations: No deviation respect to the project plan.

T4.4 – Decision tree (M4-M15) - COMPLETED
Objectives: The decision tree is the core of the IS. It will perform the data fusion between the 3 type of sensors verifying continuously the level of the radiation field with respect to the natural background. In case of an alarm, the system alerts the user allowing for a prolonged data taking in the effort of identifying the radiation source. This task requires not only the determination of the relative yield (number of fast or thermal neutrons respect the gamma-rays) but also spectroscopy of the photons. The guessed type of radiation source is displayed to the user.
Results achieved: The Decision Tree (DT) software has been realized in accordance with the specifications. All main functionalities have been implemented and were finalized as soon as the final versions of the detectors were delivered. Most of them have been previously tested using the available hardware (NaI(Tl) gamma detectors, and liquid scintillation neutron detectors). The algorithms for the source localization are under development.
Deviations: No deviation respect to the project plan.

T4.5 – Control system for the electronic front-end and DAQ (M4-M15) - COMPLETED
Objectives: The software interfaces for the management of the front-end electronics has been developed, taking into account the input from WP3. Hardware components are controlled by dedicated software interfaces.
Results achieved: The Front-End and DAQ Control System (FE&DAQ) software has been realized in accordance with the specifications. All main functionalities have been implemented and have been tested using the available CAEN front-end electronics. A custom program that handles the data transfer and the first processing of the signals inside the PC, including data reorganization and storage and, depending on the acquisition mode, quality assurance and pulse shape discrimination has been implemented as well.
Deviations: No deviation respect to the project plan.
Deliverables and Milestone:
- D4.2 – Information System Subroutines – DELIVERED ON TIME
- MS7 – Software Subroutines – DELIVERED ON TIME

T4.6 – Integration of the IS components (M16-M20) - COMPLETED
Objectives: Integration and test of the IS components developed in parallel in the tasks 4.2 4.3 4.4 and 4.5 by using data taken from the existing ARKTIS detectors as well as from standard scintillators. Quality control of the IS before the delivery to WP5.
Results achieved: the software components developed in parallel in the previous tasks have been integrated in the first release of the Information System. The IS has been tested in Padova using both the available MODES_SNM hardware and standard gamma and neutron detectors. Neutron sources as 252Cf and Am/Be and standard gamma ray sources have been employed.
Deviations: No deviation respect to the project plan.
Deliverables and Milestone:
- D4.3 – Information System – DELIVERED ON TIME

WP4 Highlights: The work package activities have proceeded as planned, and the results of the completed activities fulfill the requirements of the system and the project expectations. The first release of the IS has been tested under WP4 according with the availability of the final components of the prototype at M20. Several updated versions of the IS have been released during the following months under WP5 and WP6 according with the availability of the final hardware components and new test results. A final additional software up-date has been done at M30 after part of the field tests following the end-user suggestions. No relevant deviations with respect to the planned work happened for this WP.
WP4 Deviations: no deviations from the project plan

WP5 - Modular Detection System Design & Integration

Work package objectives: To design, construct and deliver the final fully assembly system for the lab characterization. Provide mechanical and software support during the lab characterization and field demonstration.
Deliverables
D5.1: Modular detection system available for integration – Delivered on time
D5.2: Fully integrated prototype of the modular detection system – Delivered on time

T5.1 – Design and construction of the support structure (M15-M20) - Completed
T5.1 focuses on the design and construction of the support structure. A market scan regarding the material to be used for the support structure has been performed. Composite materials offered a very elegant solution in terms of robustness, weight and stability. For the detector boxes honeycomb aluminum panel for the skin and composite aluminum panel for the end-plates have been chosen. The electronics box is made solely from composite aluminum panel. A simulation of the effect of the container’s skin to the neutron and gamma spectrum has been performed. The gamma and neutron absorption efficiency found to be small.
The design of the internal support structure for the detector and electronics boxes has also been completed. The material has been ordered and the delivery started towards the end of M20. Software and cabling have also been established.

T5.2 – Demonstrator integration (M21-M23) – Completed
At the beginning of M22 all the system components (detectors, electronics, cables and software) have been brought together for the first integration tests in ARKTIS laboratories in Zurich. The results were successful and all the components were gradually shipped to the University of Liverpool to complete the system integration. Upon arrival, all the components were installed in the dedicated boxes.
During this task, CAEN designed and produced the complete set of rugged cables for the system. This task was not planned at the beginning of the project. The consortium asked to CAEN, due to its experience in high performance electronics, to carry out this work. Special cables and connectors has been selected and the set of rugged cables was produced and tested during T5.1 permitting to complete the final integration of the system without delays.
Due to technical reasons, one gamma detector and one thermal neutron detector were not ready and agreed that these two detectors were directly shipped to the National Centre for Nuclear Research (NCBJ) in Poland. After all equipment arrived and installed in the boxes the system was powered up a few times from 30 minutes to 1 hour. No major issues recorded. All the equipment was shipped at the beginning of M24 to NCBJ.
The integration of system was completed at the beginning of M24 in NCBJ. The two detectors were installed and the fully integrated electronics and software tested again. The system was ready for the lab characterization.
After the end of M23, WP5 was extended until M27. This was needed to provide mechanical and software support during the laboratory characterization. Secondly, this extension was used to prepare a set of spare equipment in the infortune case of something was broken or not properly functioning. Finally, the time was needed also, to design and build the support structure for the van-mounted system. The support structure was prepared by the UNINS. This includes the design and construction of the rack to horizontally mount all the neutron detectors and vertically the gamma detectors (one high pressure Xenon detector and one NaI(Tl) in the final configuration). The rack was then fixed inside the van. The electronics box and the battery were also fixed at the back of the detector rack. The final integration inside the van was completed towards the end of M27.
WP5 Highlights: MODES_SNM components (detectors, electronics, computers…) travelled approximately 4500 km in different laboratories for the integration and characterization). The van mounted prototype travelled approximately 6500 km for laboratory and the field demonstration in different locations across Europe. The system was characterized by its stability and no mechanical issues were found.

WP6 Laboratory Characterization
WP6 was planned to run from M21 to M27. This work package was aimed at the performance optimization of the detectors used in the MODES_SNM prototype and the characterization of the detectors sensitivity for ionizing radiation. The work package comprised three tasks:

T6.1 - Definition of the test protocol (M21-M23) - COMPLETED
In this task the list of test measurements was prepared in order to evaluate the time needed for performance optimization of the gamma ray, fast and thermal neutron detectors. The list of necessary gamma and neutron radiation sources and shielding materials was prepared to ensure detailed characterization of the detectors responses. The activities of the sources appropriate for the prototype characterization were calculated and the sources were ordered to ensure proper radiation flux at the tested detectors at the time of tests planned during T6.2.
The test protocol for characterization of the prototype in terms of probability of detection, false alarm rate and radioisotope identification was prepared according to the requirements provided in the D1.1 Requirements Report.

T6.2 - Laboratory characterization of the prototype of Modular Detection System (M24-M26) - COMPLETED
After system integration at the NCBJ laboratory, the optimization of the detectors performance was done. The spectra were recorded with detectors under irradiation of the sources of interest to build the library for source identification. The measurements with sources listed in the test protocol were performed in order to quantify the time needed for detection of activities specified in the D1.1 Requirements Report.
After the optimization phase, the measurements were carried out in order to quantify the probability of detection, the false alarm rate and the identification of the source type for gamma ray, fast and thermal neutron detectors. In the case of gamma ray detectors, it was proved that the detectors efficiency and false alarm rate satisfy the criteria presented in the D1.1 Requirements Report. The identification tests was positive for all sources from the list, except for Co-60. Therefore it was decided to replace one of the Xe detectors with a large NaI(Tl) detector available at UNIPD, capable of identifying Co-60 source and other energetic gamma rays within the required acquisition time of 60 seconds.
In the case of fast neutron detectors both probability of detection and false alarm rate were achieved at levels required in the D1.1 Requirements Report. In the case of thermal neutron detectors, ability to identify shielded and bare neutron sources was proved.

T6.3 - Report writing (M27) - COMPLETED
In this task the results of the measurements devoted for optimization and characterization of the MODES_SNM prototype were described in details and summarized in the deliverable D6.1 Report on the Laboratory Characterization.
WP6 Highlights: The work package activities were completed as planned, and the results of the completed activities fit well with some of the requirements of the system and the project expectations as detailed in D1.1. Additional detector characterization and the qualification of the MODES_SNM prototype as a van-mounted system was performed during WP7 at the JRC-Ispra.
WP6 Deviations: no deviations from the project plan

Deliverables and Milestone:
- D6.1 – Report on the Laboratory Characterization – DELIVERED ON TIME
- MS9 – Demonstrator Characterization – DELIVERED ON TIME

WP7 Field Demonstration
Objectives of the Work Package: Field demonstration of the Modular Detection System by end-user. Test of the MMI and comparison with the requirements (WP1). WP7 was running from M25 to M30

Task 7.1 - Organization of the demonstration and definition of the protocol (M25-M26)
Objectives: Setting up of an end-user group will. Training course at the Padova University. Organization of the field demonstration.
Results achieved: It was agreed that the most efficient way to perform the field demonstration was to prepare the MODES_SNM prototype as a van-mounted system that can be operated by end-user as a stand alone system as well as in comparison with existing portals or other vehicle mounted system. An invitation letter to the European Custom organization participating to the Custom 2013 Detection Technology Experts Group was prepared and several contacts were established.
Deviations: no deviation from the project plans.

Task 7.2 - Field Demonstrations (M27-M29)
Objectives: The training course and the blind tests in laboratory conditions operated by end-users organized at the Padova University. This activity takes one working week. Field demonstrations to be organized at least in three different European locations. Each field demonstration lasts typically one week with the support of all project participants. During each field test the system will be operated by end-users only with blind tests organized by using NORM materials to avoid licensing problems.
Results achieved:
1) The van mounted system of the MODES_SNM system was prepared. A FIAT DUCATO van was rented by CAEN whereas the mechanical design for the integration of the MODES_SNM detector boxes inside the van was realized by UINS (see WP5).
2) The system was finally integrated and tested at UNIPD. The participants to the Training Course (first week of April) in Padova included the Irish Revene Commidssioners, Dutch Customs, and members of the UK Border Force (including AWE UK). The MODES_SNM Description and Operating Manual was provided to the end-users. The training course was successful, with end-users operating directly the system.
3) Field tests were organized in two seaports (Rotterdam and Dublin), a major EU airport (Heathrow, UK) and Switzerland Customs gates. The transfer of the van between the different locations was organized with the participation of all MODES_SNM participants. Immediately after the Training Course the MODES_SNM system was transferred to JRC Ispra for tests with moving sources as well as with Special Nuclear Material.
4) During the field tests the system was operated to search and identify excess radiation as the ones due to NORM materials. However, in both seaport locations, some tests with different types of radiation sources, including neutron sources, were organized directly by end-users.
5) It is worth noting that the van mounted system travelled for more than 6000 km during the field tests without showing major hardware/software problems. During the long transportation only the two gamma ray boxes were dismounted from their position. Consequently the set-up time was limited to less than 20 minutes to have the system ready for operation.
After the field tests in Rotterdam. Heathrow and Dublin, the system was first returned to the Padova University to perform some software up-grade as suggested by end-user and finally was transported to ARKTIS who performed some additional field tests at Switzerland Custom gates, taking care of the prototype storage after the end of the project.
Deviations: no deviations from the project plans

Task 7.3 - Report writing M30
Objectives: A final report describing all activities performed under this WP will be produced containing not only results from blind tests but also the feedback from the end-users about the ergonomic aspect of the system and the clarity of the man-machine interface compared to the requirements defined under WP1.
Results achieved: The end-users prepared a report in which all tests were detailed on a day-by-day basis, including comparison with existing radiation portals and/or other vehicle mounted system. Recommendations on weaknesses or possible future improvements were also issued by end-users. The report contains part of the information because of its PUBLIC nature. In any case the general results from the field tests were considered positive.
Deviations: no deviations from the project plans
WP7 Use or resources. It is worth noting that the training course was organized at the Padova University by providing to the end-user travel tickets, transportation between the Venice airport and Padova and from Padova to the Legnaro Laboratories and subsistence. The total cost of this action was about 3.6 kE. Travel expenses to drive the van between the different locations were shared among project participants.

Potential Impact:
Information Dissemination
- MODES_SNM website. At the beginning of the project, the MODES_SNM project website (http://www.modes-snm.eu) was created. Throughout the project, the website was updated. The website gives insight into the project, its goals, progress, and the consortium members. It also presents results and allows visitors to download posters and technical papers from the website.
- Press work. Consortium members announced key achievements of the MODES_SNM consortium via press releases. This was performed in full compliance with the EC's guidelines as well as the consortium's internal agreements. The MODES_SNM demonstration phase received top tier press coverage both from specialist as well as mainstream media.
- Publications and Conference Talks. A concentrated effort was made to reach both the scientific community as well as end user groups. This ongoing effort lead to the publication of MODES_SNM development results, and presentations in front of expert audiences. These activities were intensified in the second half of the project.
A list of the dissemination activities is presented in Deliverable D9.3 as well as in the SESAM online database.
It is worth mentioning that the dissemination activity #3 (5th meeting of the C2013 Customs Detection Technology expert group - Mestre/Venice (Italy) 26 and 27 June 2012) gave the opportunity to present the project to an important end-user expert group. This opened the possibility of the involvement of a number of EU custom organizations in the future project demonstration phase. In particular, the demonstration phase of the project involved a number of influential end users, to whom the results were disseminated in the process of the field demonstrations.

Market Research
The MODES_SNM consortium is dedicated to deliver upon its contractual obligation to exploit research results achieved in this program. The effort to commercially exploit MODES achievements is spearheaded by ARKTIS, supported by CAEN, the consortium's two SMEs. These have invested a significant amount of time into dedicated market research for the newly conceived products under development. This work included interviewing end users to assure alignment with their needs. Furthermore, the results are being disseminated to key international players such as the US Domestic Nuclear Detection Office and the US Second Line of Defense Program in order to increase awareness of MODES_SNM abroad, and further the understanding of our own work within an international, cross-border context.
Intellectual Property Management
A key aspect enabling successful commercial exploitation of research and development is the management of foreground IP produced within the project. For each development this involves assessing the feasibility and potential benefit of patent protection, and accordingly, taking the necessary steps to avoid nullifying patentability through premature disclosure. This fine balance has been walked by the MODES_SNM developers and researchers in close collaboration with the exploitation and dissemination board, which has screened every publication prior to release. Through diligent work on both sides, a stream of high quality papers and talks could be published without endangering future exploitation schemes.
A patent was filed on one of the developments of this project.

List of Websites:

www.modes-snm.eu