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Rosenstock W. - One of the best experts on this subject based on the ideXlab platform.
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Detection of concealed Fissionable Material by delayed neutron counting: Abstract
2009Co-Authors: Rosenstock W.Abstract:We performed measurements with a small, light-weight neutron generator, which can be carried by one person. The time structure of delayed neutrons was measured in order to detect and identify hidden or shielded nuclear Material in geometrical configurations whereof only the outer shape is known but little or no information is available on the inner structure. A small block of depleted uranium was irradiated repeatedly by a sealed neutron tube of a 14 MeV neutron generator for different time intervals. The delayed neutrons were measured by a neutron "slab" counter consisting of 6 He-3 tubes moderated by high density polyethylene. After the end of each interrogating neutron pulse we analyzed the delayed neutrons in different time intervals, ranging from 3 s to 300 s and thus recorded the "decay curves" of the delayed neutrons. We optimized neutron irradiation and measuring time to gain information on the existence of Fissionable Material in a short time. These experiments show that Fissionable Material can be detected clearly and easily in a suspicious object without any information on the inner geometry and the surrounding moderating Material within a very short time (several minutes)
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Transportable monitoring unit for detection and identification of nuclear Material
2006Co-Authors: Rosenstock W., Köble T.Abstract:The Fraunhofer-Institut für Naturwissenschaftlich-Technische Trendanalysen (INT) has developed a prototype of a transportable monitoring unit for non-destructive and non-contact analysis of radioactive Material, and Fissionable Material in particular. Passive and active nuclear radiation detection methods are used to determine the presence and type and amount of radioactive or Fissionable Materials. The purpose of this system is to assess potential risks and give recommendations for further action
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Emerging verification technologies
2006Co-Authors: Rosenstock W.Abstract:Non-intrusive verification procedures by measuring nuclear radiation in situ are discussed. Radiation measurements are decisive to prove compliance with nuclear arms control and non-proliferation in case suspicions arise at a definite locality. For that purpose we have set up a mobile measuring unit with high resolution Gamma-detectors and sensitive neutron detectors. Detection and identification of special nuclear Material is performed by non-destructive and non-contact analysis. Importance is set to the demand that systems should limit access to sensitive information, so they can be applied by NNWSs (Non Nuclear Weapon States). In addition active neutron interrogation is employed for confirmation of the existence of Fissionable Material. The capability and limits of these systems and procedures are discussed and an outlook to future developments in new detection systems and procedures is presented. In addition such systems and methods may be used in combating transnational nuclear terrorism and asymmetric warfare
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Measurement techniques to combat nuclear terrorism
2003Co-Authors: Rosenstock W., Köble T., Risse M.Abstract:To combat illicit use of nuclear and radioactive Material and to take preventive action reliable measurement techniques are imperative for early detection of this Material. Nuclear safeguards are an important tool to impede the illicit use of Fissionable Material. But only nuclear Material is controlled by safeguards, radioisotope sources are not covered by the safeguards regime in general. Whereas in most western countries comprehensive regulations for the control of radioactive Materials exist a lot of other countries have inadequate control and monitoring programs to prevent or even detect the theft of these Materials. While radiation accidents caused by orphan sources may give an idea on the extent of such a risk, the injury caused by a well planed terrorist attack with radioactive or nuclear Material may be even worse. Since the threat environment is very unpredictable mobile measuring systems are essential to detect and respond to malicious acts involving radioactive or nuclear Material. For the detection and identification of radioactive and nuclear Material Fraunhofer INT has built up a mobile measuring system integrated into a transportable container. A power generator on a trailer makes the system independent of local resources of electric power. This container as well as the power generator can be transported by land, air or sea. The system is equipped with various types of detectors for neutron and gamma radiation, some of the detectors are similar to those used in safeguards. The type of radiation and its activity level can be determined. In case of neutron emitting Material it is possible to distinguish Fissionable Material from random neutron sources by means of coincidence counting. This system is completed by a measurement car, which is equipped with high efficient neutron detectors and a background subtracting gamma measurement system. With this system hidden radioactive Material can also be revealed by a covered search. In case of a radiological dispersal device or an improvised nuclear device the danger zone may extend to several hundred meters. In this case the detectors and electronics are moved with a remote controlled manipulator vehicle near the suspicious object. The measured data are transferred via radio transmission to the container placed in a safe distance for evaluation and risk assessment. Depending on availability of telecommunication infrastructure, the measurement results can be communicated by telephone line, mobile phone or satellite. Based on the results the next action steps are decided by law enforcement authorities. The capabilities of these mobile detection systems have been demonstrated in field exercises. Details of on-site identification measurements and results will be presented
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Detecting Fissionable Material from a travelling vehicle by neutron coincidence measurements
2002Co-Authors: Köble T., Rosenstock W., Risse M., Engelen-peter J.Abstract:For the search and detection of concealed nuclear Material we equipped a conventional car with a neutron measurement system. It consists of six neutron slab counters on each side and the appropriate electronics. The complete system can easily be fixed in most vehicles. The pulses of the six modules on each side are summed passively and each side is analyzed separately. The results are displayed on a handheld pe in the front of the car or, in case of a covered search, the data are stored in a non-volatile memory together with coordinate information from GPS. In order to verify the presence of Fissionable Material, we investigated the possibility to detect two or more neutrons in coincidence. In this way it is possible to distinguish industrial neutron sources like Am/Be(n) from Special Nuclear Material. First the Material is localized by its total rate from the moving vehicle. Then the vehicle is stopped in the vicinity of the suspicious location and the coincidences are counted for a period of 10 to 1000 seconds depending on neutron intensity and distance. At a distance of I meter, a quantity of gof weapon-grade plutonium can be detected in 1000 seconds, corresponding to 0.5 g reactor plutonium, in 10 seconds the detection limit is 200 g. In case of a concrete shielding of 10 cm thickness the detection limit is increased to 6.3 g in 1000 seconds and OA7 kg for an interval of 10 seconds. With 20 cm concrete shielding these values are approximately doubled. Larger quantities of weapon-grade or reactor plutonium (kilograms) can also be identified out of the moving vehicle. This system may be used to discover illicit trafficking of nuclear Material and thus prohibit nuclear proliferation
E H Seabury - One of the best experts on this subject based on the ideXlab platform.
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addressing different active neutron interrogation signatures from Fissionable Material
IEEE Nuclear Science Symposium, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:In a continuing effort to examine portable methods for implementing active neutron interrogation for detecting shielded Fissionable Material research is underway to investigate the utility of analyzing multiple time-correlated signatures. Time correlation refers here to the existence of unique characteristics of the fission interrogation signature related to the start and end of an irradiation, as well as signatures present in between individual pulses of an irradiating source. Traditional measurement approaches in this area have typically worked to detect die-away neutrons after the end of each pulse, neutrons in between pulses related to the decay of neutron emitting fission products, or neutrons or gamma rays related to the decay of neutron emitting fission products after the end of an irradiation exposure. In this paper we discus the potential weaknesses of assessing only one signature versus multiple signatures and make the assertion that multiple complimentary and orthogonal measurements should be used to bolster the performance of active interrogation systems, helping to minimize susceptibility to the weaknesses of individual signatures on their own. Recognizing that the problem of detection is a problem of low count rates, we are exploring methods to integrate commonly used signatures with rarely used signatures to improve detection capabilities for these measurements. In this paper we will discuss initial activity in this area with this approach together with observations of some of the strengths and weaknesses of using these different signatures.
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active neutron interrogation to detect shielded Fissionable Material
International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators Vienna Austria 05 04 2009 05 08 2009, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:Portable electronic neutron generators (ENGs) may be used to interrogate suspicious items to detect, characterize, and quantify the presence Fissionable Material based upon the measurement of prompt and/or delayed emissions of neutrons and/or photons resulting from fission. The small size (<0.2 m3), light weight (<12 kg), and low power consumption (<50 W) of modern ENGs makes them ideally suited for use in field situations, incorporated into systems carried by 2-3 individuals under rugged conditions. At Idaho National Laboratory we are investigating techniques and portable equipment for performing active neutron interrogation of moderate sized objects less than ~2-4 m3 to detect shielded Fissionable Material. Our research in this area relies upon the use of pulsed deuterium-tritium ENGs and the measurement of die-away prompt fission neutrons and other neutron signatures in-between neutron pulses from the ENG and after the ENG is turned off.
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Using Electronic Neutron Generators in Active Interrogation to Detect Shielded Fissionable Material
IEEE Transactions on Nuclear Science, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded Fissionable Material. Here we report initial work using a portable DT electronic neutron generator with a 3He neutron detector to detect shielded Fissionable Material including enriched uranium and reactor grade plutonium. Measurements have been taken of bare Material as well as of Material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear Material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 times 108 neutrons per second, 2.2 kg of enriched uranium hidden within a 61 cm times 61 cm times 71 cm volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit approaching the gram level could be expected with the same simple set-up.
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Using electronic neutron generators in active interrogation to detect shielded Fissionable Material
2008 IEEE Nuclear Science Symposium Conference Record, 2008Co-Authors: D L Chichester, E H SeaburyAbstract:Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded Fissionable Material. Here we report initial work using a portable DT electronic neutron generator with a He-3 fast neutron detector to detect shielded Fissionable Material including enriched uranium and reactor grade plutonium. Measurements have been taken of bare Material as well as of Material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear Material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 x 108 neutrons per second, 2.2 kg of enriched uranium hidden within a 0.60 m x 0.60 m x 0.70 m volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit of approaching the gram level could be expected with the same simple set-up.
D L Chichester - One of the best experts on this subject based on the ideXlab platform.
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addressing different active neutron interrogation signatures from Fissionable Material
IEEE Nuclear Science Symposium, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:In a continuing effort to examine portable methods for implementing active neutron interrogation for detecting shielded Fissionable Material research is underway to investigate the utility of analyzing multiple time-correlated signatures. Time correlation refers here to the existence of unique characteristics of the fission interrogation signature related to the start and end of an irradiation, as well as signatures present in between individual pulses of an irradiating source. Traditional measurement approaches in this area have typically worked to detect die-away neutrons after the end of each pulse, neutrons in between pulses related to the decay of neutron emitting fission products, or neutrons or gamma rays related to the decay of neutron emitting fission products after the end of an irradiation exposure. In this paper we discus the potential weaknesses of assessing only one signature versus multiple signatures and make the assertion that multiple complimentary and orthogonal measurements should be used to bolster the performance of active interrogation systems, helping to minimize susceptibility to the weaknesses of individual signatures on their own. Recognizing that the problem of detection is a problem of low count rates, we are exploring methods to integrate commonly used signatures with rarely used signatures to improve detection capabilities for these measurements. In this paper we will discuss initial activity in this area with this approach together with observations of some of the strengths and weaknesses of using these different signatures.
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active neutron interrogation to detect shielded Fissionable Material
International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators Vienna Austria 05 04 2009 05 08 2009, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:Portable electronic neutron generators (ENGs) may be used to interrogate suspicious items to detect, characterize, and quantify the presence Fissionable Material based upon the measurement of prompt and/or delayed emissions of neutrons and/or photons resulting from fission. The small size (<0.2 m3), light weight (<12 kg), and low power consumption (<50 W) of modern ENGs makes them ideally suited for use in field situations, incorporated into systems carried by 2-3 individuals under rugged conditions. At Idaho National Laboratory we are investigating techniques and portable equipment for performing active neutron interrogation of moderate sized objects less than ~2-4 m3 to detect shielded Fissionable Material. Our research in this area relies upon the use of pulsed deuterium-tritium ENGs and the measurement of die-away prompt fission neutrons and other neutron signatures in-between neutron pulses from the ENG and after the ENG is turned off.
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Using Electronic Neutron Generators in Active Interrogation to Detect Shielded Fissionable Material
IEEE Transactions on Nuclear Science, 2009Co-Authors: D L Chichester, E H SeaburyAbstract:Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded Fissionable Material. Here we report initial work using a portable DT electronic neutron generator with a 3He neutron detector to detect shielded Fissionable Material including enriched uranium and reactor grade plutonium. Measurements have been taken of bare Material as well as of Material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear Material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 times 108 neutrons per second, 2.2 kg of enriched uranium hidden within a 61 cm times 61 cm times 71 cm volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit approaching the gram level could be expected with the same simple set-up.
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Using electronic neutron generators in active interrogation to detect shielded Fissionable Material
2008 IEEE Nuclear Science Symposium Conference Record, 2008Co-Authors: D L Chichester, E H SeaburyAbstract:Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded Fissionable Material. Here we report initial work using a portable DT electronic neutron generator with a He-3 fast neutron detector to detect shielded Fissionable Material including enriched uranium and reactor grade plutonium. Measurements have been taken of bare Material as well as of Material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear Material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 x 108 neutrons per second, 2.2 kg of enriched uranium hidden within a 0.60 m x 0.60 m x 0.70 m volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit of approaching the gram level could be expected with the same simple set-up.
G J Mauger - One of the best experts on this subject based on the ideXlab platform.
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the nuclear car wash a system to detect nuclear weapons in commercial cargo shipments
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2007Co-Authors: D R Slaughter, M R Accatino, A Bernstein, J A Church, Marieanne Descalle, D Manatt, G J Mauger, J Hall, P Biltoft, T MooreAbstract:Abstract A concept for detecting the presence of special nuclear Material (235U or 239Pu) concealed in intermodal cargo containers has been developed, studied, and recent performance results are described. It is based on interrogation with a pulsed beam of 3–7 MeV neutrons that produce fission events and subsequent detection of their β-delayed neutron emission or β-delayed high-energy γ-radiation reveals the presence of Fissionable Material. Fission product β-delayed γ-rays above 3 MeV are nearly 10 times more abundant than β-delayed neutrons and are distinct from natural radioactivity and from nearly all of the induced activity in a normal cargo. Detector backgrounds and potential interferences with the fission signature radiation have been identified and quantified. Their impact on detection sensitivity is relatively minor and can be addressed readily. Components of a simple laboratory prototype have been assembled, tested with the most challenging cargo threat scenarios, and results compared to computer simulations. Preliminary results will be presented.
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preliminary results utilizing high energy fission product γ rays to detect Fissionable Material in cargo
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2005Co-Authors: D Slaughter, M R Accatino, A Bernstein, J A Church, Marieanne Descalle, Thomas B Gosnell, J M Hall, A Loshak, D Manatt, G J MaugerAbstract:Abstract A concept for detecting the presence of special nuclear Material (235U or 239Pu) concealed in intermodal cargo containers is described. It is based on interrogation with a pulsed beam of 7 MeV neutrons that produce fission events and their β-delayed neutron emission or β-delayed high-energy γ radiation between beam pulses provide the detection signature. Fission product β-delayed γ-rays above 3 MeV are nearly 10 times more abundant than β-delayed neutrons and are distinct from natural radioactivity and from nearly all of the induced activity in a normal cargo. Detector backgrounds and potential interferences with the fission signature radiation have been identified and quantified.
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early results utilizing high energy fission product gamma rays to detect Fissionable Material in cargo
Nuclear Instruments & Methods B vol. 241 no. 1-4 August 30 2005 pp. 777-781, 2004Co-Authors: D R Slaughter, M R Accatino, A Bernstein, Marieanne Descalle, Thomas B Gosnell, A Loshak, D Manatt, Jennifer Church, J Hall, G J MaugerAbstract:A concept for detecting the presence of special nuclear Material ({sup 235}U or {sup 239}Pu) concealed in intermodal cargo containers is described. It is based on interrogation with a pulsed beam of 7 MeV neutrons that produce fission events and their {beta}-delayed neutron emission or {beta}-delayed high-energy {gamma}-radiation between beam pulses provide the detection signature. Fission product {beta}-delayed {gamma}-rays above 3 MeV are nearly ten times more abundant than {beta}-delayed neutrons and are distinct from natural radioactivity and from nearly all of the induced activity in a normal cargo. Detector backgrounds and potential interferences with the fission signature radiation have been identified and quantified. An important goal in the US is the detection of nuclear weapons or special nuclear Material (SNM) concealed in intermodal cargo containers. This must be done with high detection probability, low false alarm rates, and without impeding commerce, i.e. about one minute for an inspection. The concept for inspection has been described before and its components are now being evaluated. While normal radiations emitted from plutonium may allow its detection, the majority of {sup 235}U {gamma} ray emission is at 186 keV, is readily attenuated by cargo, and thus not a reliable detection signature for passivemore » detection. Delayed neutron detection following a neutron or photon beam pulse has been used successfully to detect lightly or unshielded SNM targets. While delayed neutrons can be easily distinguished from beam neutrons they have relatively low yield in fission, approximately 0.008 per fission in {sup 239}Pu and 0.017 per fission in {sup 235}U, and are rapidly attenuated in hydrogenous Materials making that technique unreliable when challenged by thick hydrogenous cargo overburden. They propose detection of {beta}-delayed high-energy {gamma} radiation as a more robust signature characteristic of SNM.« less
Köble T. - One of the best experts on this subject based on the ideXlab platform.
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Transportable monitoring unit for detection and identification of nuclear Material
2006Co-Authors: Rosenstock W., Köble T.Abstract:The Fraunhofer-Institut für Naturwissenschaftlich-Technische Trendanalysen (INT) has developed a prototype of a transportable monitoring unit for non-destructive and non-contact analysis of radioactive Material, and Fissionable Material in particular. Passive and active nuclear radiation detection methods are used to determine the presence and type and amount of radioactive or Fissionable Materials. The purpose of this system is to assess potential risks and give recommendations for further action
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Measurement techniques to combat nuclear terrorism
2003Co-Authors: Rosenstock W., Köble T., Risse M.Abstract:To combat illicit use of nuclear and radioactive Material and to take preventive action reliable measurement techniques are imperative for early detection of this Material. Nuclear safeguards are an important tool to impede the illicit use of Fissionable Material. But only nuclear Material is controlled by safeguards, radioisotope sources are not covered by the safeguards regime in general. Whereas in most western countries comprehensive regulations for the control of radioactive Materials exist a lot of other countries have inadequate control and monitoring programs to prevent or even detect the theft of these Materials. While radiation accidents caused by orphan sources may give an idea on the extent of such a risk, the injury caused by a well planed terrorist attack with radioactive or nuclear Material may be even worse. Since the threat environment is very unpredictable mobile measuring systems are essential to detect and respond to malicious acts involving radioactive or nuclear Material. For the detection and identification of radioactive and nuclear Material Fraunhofer INT has built up a mobile measuring system integrated into a transportable container. A power generator on a trailer makes the system independent of local resources of electric power. This container as well as the power generator can be transported by land, air or sea. The system is equipped with various types of detectors for neutron and gamma radiation, some of the detectors are similar to those used in safeguards. The type of radiation and its activity level can be determined. In case of neutron emitting Material it is possible to distinguish Fissionable Material from random neutron sources by means of coincidence counting. This system is completed by a measurement car, which is equipped with high efficient neutron detectors and a background subtracting gamma measurement system. With this system hidden radioactive Material can also be revealed by a covered search. In case of a radiological dispersal device or an improvised nuclear device the danger zone may extend to several hundred meters. In this case the detectors and electronics are moved with a remote controlled manipulator vehicle near the suspicious object. The measured data are transferred via radio transmission to the container placed in a safe distance for evaluation and risk assessment. Depending on availability of telecommunication infrastructure, the measurement results can be communicated by telephone line, mobile phone or satellite. Based on the results the next action steps are decided by law enforcement authorities. The capabilities of these mobile detection systems have been demonstrated in field exercises. Details of on-site identification measurements and results will be presented
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Detecting Fissionable Material from a travelling vehicle by neutron coincidence measurements
2002Co-Authors: Köble T., Rosenstock W., Risse M., Engelen-peter J.Abstract:For the search and detection of concealed nuclear Material we equipped a conventional car with a neutron measurement system. It consists of six neutron slab counters on each side and the appropriate electronics. The complete system can easily be fixed in most vehicles. The pulses of the six modules on each side are summed passively and each side is analyzed separately. The results are displayed on a handheld pe in the front of the car or, in case of a covered search, the data are stored in a non-volatile memory together with coordinate information from GPS. In order to verify the presence of Fissionable Material, we investigated the possibility to detect two or more neutrons in coincidence. In this way it is possible to distinguish industrial neutron sources like Am/Be(n) from Special Nuclear Material. First the Material is localized by its total rate from the moving vehicle. Then the vehicle is stopped in the vicinity of the suspicious location and the coincidences are counted for a period of 10 to 1000 seconds depending on neutron intensity and distance. At a distance of I meter, a quantity of gof weapon-grade plutonium can be detected in 1000 seconds, corresponding to 0.5 g reactor plutonium, in 10 seconds the detection limit is 200 g. In case of a concrete shielding of 10 cm thickness the detection limit is increased to 6.3 g in 1000 seconds and OA7 kg for an interval of 10 seconds. With 20 cm concrete shielding these values are approximately doubled. Larger quantities of weapon-grade or reactor plutonium (kilograms) can also be identified out of the moving vehicle. This system may be used to discover illicit trafficking of nuclear Material and thus prohibit nuclear proliferation
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Measurement of the time structure of delayed neutrons after induced fission in special nuclear Material
1999Co-Authors: Hilger P., Köble T., Rosenstock W.Abstract:Nondestructive measuring capabilities were investigated for the in situ detection and analysis of special nuclear Material, which is surrounded by additional shielding thus impeding direct detection. We performed measurements of the time structure of delayed neutrons in order to detect and identify hidden or shielded nuclear Material in geometrical configurations, which are not known in detail. A block of depleted uranium was irradiated repeatedly with our 14 MeV neutron generator for different time intervals. After the end of the interrogating neutron pulse we integrated the delayed neutrons in different time intervals and thus recorded the "decay curves". The distance from the neutron tube to the object was varied to simulate measurement under difficult spatial conditions. Detection within a distance of several meters is possible. To enhance the detection efficiency we optimized the thickness of the polyethylene (PE) moderator of the neutron detector for delayed neutrons. The experimental data were compared with MCNP calculations. To obtain information on the existence of Fissionable Material in a short time we optimized neutron irradiation and integration time. These experiments show that Fissionable Material can be detected clearly and easily in a suspicious box without information on the geometry within a very short time (several minutes)
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Measurement of delayed neutrons after induced fission of special nuclear Material
1997Co-Authors: Rosenstock W., Köble T., Kruzinski G., Kobus H.Abstract:Nondestructive measuring capabilities for the in situ detection and analysis of nuclear Material are considered as possible measures to discover illicit trafficking of nuclear Material and to prohibit nuclear proliferation. Therefore, we performed measurements on the time structure of delayed neutrons after the induced fission of nuclear Material by a pulsed 14 MeV neutron tube. The measured decay curves were fitted to the well known six groups of delayed neutrons. The relative strengths of the differenum isotopes. Thinking of verfification of weapons Materials this measurement method allows confirmation of fissile Materials content without disclosing sensitive information (like geometry). These experiments show that Fissionable Material can be detected clearly and easily in a suspicious box with a pulsed neutron generator within a very short time (several minutes)