The Second Line of Defense program has deployed a worldwide
network of Radiation Portal Monitors to help stop the illicit
trafficking of radioactive material. The detection of this
type of material can be affected by the spatial and temporal
changes in natural background radiation (NBR). Work on this
project has focused on NBR effects caused by building materials
used in the construction of the roadbed and surrounding
structures. Concrete core samples were taken from the ORNL
portal test area and delivered to TAMU. The NBR of the
samples was measured using an HPGe detector. Neutron
Activation Analysis was conducted on the samples to determine their
elemental composition. In addition, radiographs of the
samples were taken to determine their internal structure.
From this information a student using MCNP, was able to construct a
radiation transport simulation using an accurate representation of
NBR isotopes in the concrete. Eventually the techniques and
simulations developed from this study will help predict RPM
response before construction begins.
Following the radiography of the core samples to determine the
internal structure, accurate ISOCS modules will by generated.
This will allow more accurate spectral analysis of the concrete to
determine the NBR content. These results will be used to
refine the existing MCNP model. The model will be benchmarked
against field measurements from the ORNL test bed. The
simulations resulting from this work will be useful tools for the
Second Line of Defense program to determine NBR around radiation
- M.B. Fitzmaurice, C.M. Marianno, and A.A. Solodov ,
"Developing a Methodology for Determination of Elemental Composition of Shielding Materials,"
Journal of Health Physics 109:4 (2016).
- C.M. Ryan, C.M. Marianno, W.S. Charlton, A.A. Solodov, J. Livesay, and B. Goddard,
" Predicting Concrete Roadway Contribution to Gamma-ray Background in Radiation Portal Monitor Systems,"
Nuclear Technology 186:3 (2014). See Document
- J.M. Osborn, C.M. Marianno, A.A. Solodov, and W.S. Charlton,
"Concrete Characterization Using Gamma-ray Interaction Methods,"
Proceedings of 53rd Annual Meeting of the Institute of Nuclear Material Management, Orlando, FL, July 15-19, 2012.
- M.B. Fitzmaurice, A.A. Solodov, C.M. Marianno, W.S. Charlton, J. Livesay, and T. Guzzardo.,
"Developing a Methodology for Characterization of Building Materials' Natural Radiation Background and Integration into an MCNP Model for Radiation Portal Monitoring Systems,"
53rd Annual Meeting of the Institute of Nuclear Materials Management, Orlando, Florida, 15-19 July 2012.
- C.M. Ryan, C.M. Marianno, W.S. Charlton and W.D. James,
"Neutron activation analysis of concrete for cross-border nuclear security,"
Journal of Radioanalytical and Nuclear Chemistry 291, 267-272 (2012). See Document
- C.M. Marianno and C.M. Ryan,
"Examining a Potential Technique to Determine Gamma-Ray Background for Radiation Portal,"
Canberra Users Group Meeting, Dallas, TX, July 11-15, 2011.
- C.M. Ryan, C.M. Marianno, W.S. Charlton, A.A. Solodov, and R.J. Livesay,
"Determining the Effect of Concrete Roadways on Gamma-ray Background for Radiation Portal Monitoring Systems,"
33rd ESARDA Annual Meeting: Symposium on Safeguards and Nuclear Material Management, May 16–20, 2011, Budapest, Hungary. See Document
- C.M. Ryan, C.M. Marianno, W.S. Charlton, and W.D. James,
"Neutron Activation Analysis of Concrete for Cross-Border Nuclear Security,"
13th International Conference on Modern Trends in Activation Analysis, College Station, TX, March 13-18, 2011.
- C.M. Ryan, C.M. Marianno, W.S. Charlton, A.A. Solodov, J. Livesay,
"Determining the Effects of Construction Materials on Background Readings for Second Line of Defense Program Portal Monitoring Systems,"
Proceedings of the 51st Annual Meeting of the Institute of Nuclear Materials and Management, Baltimore, MD, USA, July 11-15, 2010. See Document
Powdered Concrete Samples Used for Experiments