A protocol for the production of synthetic nuclear melt glass, similar to trinitite, is presented.
Realistic surrogate nuclear debris is needed within the nuclear forensics community to test and validate post-detonation analysis techniques. Here we outline a novel process for producing bulk surface debris using a high temperature furnace. The material developed in this study is physically and chemically similar to trinitite (the melt glass produced by the first nuclear test). This synthetic nuclear melt glass is assumed to be similar to the vitrified material produced near the epicenter (ground zero) of any surface nuclear detonation in a desert environment. The process outlined here can be applied to produce other types of nuclear melt glass including that likely to be formed in an urban environment. This can be accomplished by simply modifying the precursor matrix to which this production process is applied. The melt glass produced in this study has been analyzed and compared to trinitite, revealing a comparable crystalline morphology, physical structure, void fraction, and chemical composition.
Concerns over the potential malicious use of nuclear weapons by terrorists or rogue nations have highlighted the importance of nuclear forensics analysis for the purpose of attribution.1 Rapid post-detonation analysis techniques are desirable to shorten the attribution timeline as much as possible. The development and validation of such techniques requires realistic nuclear debris samples for testing. Nuclear testing no longer occurs in the United States and nuclear surface debris from the testing era is not readily available (with the exception of trinitite – the melt glass produced by the first nuclear test at the trinity site) and therefore realistic surrogate debris is needed.
The primary goal of the method described here is the production of realistic surrogate nuclear debris similar to trinitite. Synthetic nuclear melt glass samples which are readily available to the academic community can be used to test existing analysis techniques and to develop new methods such as thermo-chromatography for rapid post-detonation analysis.2 With this goal in mind the current study is focused on producing samples which mimic trinitite but do not contain any sensitive weapon design information. The fuel and tamper components within these samples are completely generic and the comparison to trinitite is based on chemistry, morphology, and physical characteristics. The similarities between trinitite and the synthetic nuclear melt glass produced in this study have been previously discussed.3
The purpose of this article is to outline the details of the production process used at the University of Tennessee (UT). This production process was developed with two key parameters in mind: 1) the composition of material incorporated into nuclear melt glass, and 2) the melting temperature of the material. Methods exist for estimating the melting temperature of glass forming networks4 and these techniques have been employed here, along with additional experimentation to determine the optimal processing temperature for the trinitite matrix.5
Alternative methods for surrogate debris production have been published recently. The use of high power lasers has the advantage of creating sufficiently high temperatures to cause elemental fractionation within the target matrix.6 Porous chromatographic substrates have been used to produce small particles similar to fallout particles using condensed phase methods7. The latter method is most useful for producing particulate debris (nuclear fallout) and has been demonstrated with natural metals. The advantages of the method presented here are 1) simplicity, 2) reproducibility, and 3) scalability (sample sizes can range from tiny beads to large chunks of melt glass). Also, this method is expandable both in terms of production output and variety of explosive scenarios covered, and it has already been demonstrated using radioactive materials. A sample has been successfully activated at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). Natural uranium compounds were added to the matrix prior to melting and fission products were produced in situ by neutron irradiation.
Methods within the glass making industry and those employed for the purpose of radioactive waste immobilization8 have been consulted in the development of the method presented here. The unique effects of radiation in glasses are of inherent interest9 and will constitute an important area of study as this method is further developed.
The method described below is appropriate for any application where a bulk melt glass sample is desired. These samples most closely resemble the material found near the epicenter of a nuclear explosion. Samples of various sizes can be produced, however, methods employing plasma torches or lasers will be more useful for simulating fine particulate debris. Also, commercial HTFs do not reach temperatures high enough to cause elemental fractionation for a wide range of elements. This method should be employed when physical and morphological characteristics are of primary importance.
Bemærkning vedrørende trin 1.2.2 og 1.2.3: Den nøjagtige mængde UNH vil variere afhængigt af scenariet simuleres. Planlægning formler udviklet af Giminaro et al. Kan bruges til at vælge den rette massen af uran til en given prøve 13, som omtalt i afsnittet dette papir "Sample aktivering". Ligeledes kan uran oxid (UO 2 eller U 3 O 8) bruges i stedet for UNH, hvis de er tilgængelige, og massen brøkdel af 235 U i forbindelsen (uanset om UNH…
The authors have nothing to disclose.
Portions of this study have been previously published in the Journal of Radioanalytical and Nuclear Chemistry.3,13 A patent is pending for this method.
High Temperature Furnace (HTF) | Carbolite | HTF 18 | 1800C HTF used to melt samples |
High Temperature Drop Furnace | CM Inc. | 1706 BL | 1700C Drop Furnace used to melt samples |
Graphite Crucibles | SCP Science | 040-060-041 | 27 mL high purity graphite crucibles (10 pack) |
Crucible Tongs | Grainger | 5ZPV0 | 26 in, stainless steele tongs for handling crucibles |
Heat Resistent Gloves | Grainger | 8814-09 | Gloves used to protect hands from heat during sample intro/removal |
Mortar & Pestle | Fisherbrand | S337631 | 300 mL, Ceramic mortar and pestle for powdering and mixing |
Micro Balance | Grainger | 8NJG2 | 220g Cap, high precision scale for measuring powder mass |
Spatulas | Fisherbrand | 14374 | Metal spatulas for measure small quantities of powder |
SiO2 | Sigma-Aldrich | 274739-5KG | Quartz Sand CAS Number: 14808-60-7 |
Al2O3 | Sigma-Aldrich | 11028-1KG | Aluminum Oxide Powder CAS Number: 1344-28-1 |
CaO | Sigma-Aldrich | 12047-2.5KG | Calcium Oxide Powder CAS Number: 1305-78-8 |
FeO | Sigma-Aldrich | 400866-25G | Iron Oxide Powder CAS Number: 1345-25-1 |
MgO | Sigma-Aldrich | 342793-250G | Magnesium Oxide Powder CAS Number: 1309-48-4 |
Na2O | Sigma-Aldrich | 36712-25G | Sodium Oxide Powder CAS Number: 1313-59-3 |
KOH | Sigma-Aldrich | 278904-250G | Potasium Hydroxide Pellets CAS Number: 12030-88-5 |
MnO | Sigma-Aldrich | 377201-500G | Manganese Oxide Powder CAS Number: 1344-43-0 |
TiO2 | Sigma-Aldrich | 791326-5G | Titanium Oxide Beads CAS Number: 12188-41-9 |