Conveners
T4.1 e-poster session: e-poster session - T4.1 - Performance Evaluation and Modelling of the Full Verification System and its Components
- Thierry Heritier (CTBTO Preparatory Commission, Vienna, Austria)
T4.1 e-poster session: T4.1 - Performance Evaluation and Modelling of the Full Verification System and its Components
- Thierry Heritier (CTBTO Preparatory Commission, Vienna, Austria)
Description
T4.1
The results of testing, at the Australian NDC, of the NDC-in-a-Box (NIAB) release containing the NET-VISA associator integrated with SeisComp3 (SC3) are presented. The aim of this work was twofold: First to test how well the NIAB release was able to reproduce the VSEL3 bulletin produced by the International Data Centre (IDC) using data from the IMS network of stations. Second, to use an...
Quality control (QC) in beta-gamma coincidence systems that are used for radioxenon measurement is currently performed using a Cs-137 check source. Compton scattering in the scintillating plastic (polyvinyl-toluene) of the beta detector creates a line of activity from the 667 keV gamma captured by the sodium iodide (NaI) across the beta dynamic range. Fitting the Compton scatter line provides...
The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) has been developing and testing NET-VISA, Bayesian automatic waveform event detector, whilst a conventional detector, Global Association (GA), is in operation. In the context of CTBT verification regime, knowing the location dependency of the minimum detectable magnitude of those two event detectors...
World War 2 (WW2) devastated Europe between 1939 and 1945. Unexploded ordnances remaining from this conflict are still found in European harbours. These recovered ordnances are moved to remote locations and destroyed in a controlled way. Some underwater detonations were large enough to be recorded by the International Monitoring System (IMS). Related events were included in the International...
The PTS is leading the IDC SHI Reengineering project since 2014 with the goal of creating modernized, open-source software for SHI processing, and improving maintainability and extensibility to the system. Starting 2019, the project entered the Implementation phase and is currently under active development. The future system is based on the Geophysical Monitoring System (GMS) being developed...
The IDC investigates the utilization of High-Resolution Atmospheric Transport Modelling (HRATM) in the CTBTO’s aim to locate possible source regions after detections of radioactive substances through the International Monitoring System (IMS). Supporting the decision process, the IDC accomplished a case study with two approaches; using the current operational atmospheric transport model...
The question of whether the increased cost of implementing higher input resolutions in atmospheric transport models is difficult to address, and any answer is typically qualified with an “it depends.” Attempts to study the effects of high resolution are frequently performed with a small set of case studies, making it difficult to generalise the findings to other cases that may vary in a...
Following the statement of the state of Raetia regarding an accident at a TRIGA reactor facility, the Austrian NDC started investigating a possible violation of the Test-Ban Treaty. Based on a list of IMS radionuclide detections a forward run was performed and Possible Source Regions were determined. However, the detections could not be traced back unambiguously to the location of the reactor....
In the verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), nuclear tests must be detected and identified with high confidence. Seismic monitoring is particularly well suited for detecting and locating an underground nuclear explosion and determining its magnitude. The detection capability of a seismic network depends on the density of the network and distribution of...
The Wilson Alaska Technical Center (WATC) at the University of Alaska Fairbanks operates a worldwide set of primary seismic, auxiliary seismic, and infrasound stations for the US Nuclear Arms Control Technology (NACT) Program and CTBTO. While WATC has long employed tools focused on data integrity, this project has expanded the quality control scheme to include data quality metrics that...
The consistency of phases is an important method to estimate the relationship between the event and signal in the detection of seismic event. The consistency of amplitude can be used to determine the association, through the comparison of amplitude residuals, of numerous signal features on time and frequency domain. Different phases comply with the different propagation and attenuation laws of...
The NDC Preparedness Exercises (NPE) are regularly performed dealing with fictitious treaty violations to practice the combined analysis of CTBT verification technologies. These exercises should help to evaluate the effectiveness of analysis procedures applied at NDCs and the quality, completeness and usefulness of IDC products. The NPE2019 is a combined radionuclide-waveform scenario. The...
The CTBTO PrepCom and the Government of Italy agreed that the seismic station located in Cludinico (CLUD) may participate as a prototype Cooperating National Facility (CNF) in experiment conducted by the Commission. The Government of Italy designed the National Institute of Oceanography and Applied Geophysics – OGS (Italy) as responsible for the management of the station. This station can...
The SSI calibration module is a tool that extends the Standard Station Interface (SSI) for intuitive execution of instrumental calibrations and review of calibration results. It aims to support the complex planning, technical execution, evaluation and reporting of the calibration of IMS seismic and T-phase stations. The SSI calibration module also provides a single and standard interface that...
Two principal performance measures of the International Monitoring System (IMS) stations detection capability are the rate of automatic detections associated with events in the Reviewed Event Bulletin (REB) or precision of the REB and the rate of detections manually added to the REB or miss rate of the REB. These two metrics are significantly influenced by prespecified slowness-, frequency-...
As of 14 December 2020, almost 90% of the IMS facilities (including radionuclide laboratories) were installed and certified, data is transmitted in either real time or on request from IMS stations to IDC for processing and analyzing. IDC analysts review automatic bulletins generated continuously and release the Reviewed Event Bulletin (REB) on a daily basis since February 2000. We present the...
National Data Centre (NDC) staff need to interpret International Data Centre (IDC) seismic, hydroacoustic, and infrasonic (SHI) data processing results, which requires detailed knowledge of IDC SHI data processing. Similar understanding is needed by those that want to propose new IDC SHI data processing algorithms. To find the required information, NDC staff access the “IDC Processing of SHI...
