Radiation dosimetry of a graphite moderated radium-beryllium source
Holden, N.E.; Reciniello, R.N.; Hu, J.-P.
Health Physics 86(5 Suppl): S110-S112
2004
ISSN/ISBN: 0017-9078 PMID: 15069300 Document Number: 569613
The Brookhaven National Laboratory Sigma Pile is a radium-beryllium neutron source imbedded in a cube of graphite blocks. The pile is approximately 2.13 m on four sides and is 3.07 m high. Thermoluminescent dosimeters were used to determine the neutron and gamma-ray dose rates in the pile. Gamma-ray dose rate measurements have also been made in the air outside of the pile, while the radium-beryllium neutron source was being withdrawn from the pile. The Monte Carlo code has been used to calculate the coupled neutron-photon transport. Measured dose rates at various locations agreed with the calculated values within 5% to 15%.