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Search Publications by: C. Michelle O'Brien (Fed)

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Displaying 1 - 17 of 17

SIM.RI(I)-K3 Comparison of Calibration Coefficients at Radiotherapy Level for Orthovoltage X-ray Beams

February 2, 2015
Author(s)
C M. O'Brien, J.P. McCaffrey, H Shen, M Saravi, G M. Ortiz, G Stefanic, M Carlos, C.N.M. da Silva, J L. Alvarez, V Tovar
Air-kerma calibration coefficients were compared at the radiotherapy level for orthovoltage x-ray beams in the SIM.RI(I)-K3 comparison for members of the Sistema Interamericano de Metrología (SIM). Five SIM laboratories participated in the comparison: NIST

New National Air-Kerma Standard for Low-Energy Electronic Brachytherapy Sources

October 6, 2014
Author(s)
Stephen M. Seltzer, C M. O'Brien, Michael G. Mitch
The purpose of this report is to document the NIST air-kerma measurement standard for the electronic brachytherapy sources, i.e., the Axxent sources of Xoft, Inc., which operate at tube potentials of 50 kV and anode currents of 300 μA. The use of such

Comparison of the NIST and PTB Standards for Air Kerma and Low-Energy X-rays

December 31, 2009
Author(s)
C M. O'Brien, L. Buermann
A comparison has been made of the air-kerma standards for low-energy x-rays at the National Institute of Standards and Technology (NIST) and the Physikalisch-Technische Bundesanstalt (PTB). The comparison involved a series of measurements at the PTB and

Comparison of national air kerma standards for ISO 4037 narrow spectrum series in the range 30 kV to 300 kV.

February 1, 2009
Author(s)
C M. O'Brien, L. Buermann, P. Butler, I. Csete, F. Gabris, A. Hakanen, J. -. Lee, M. Palmer, N. Saito, W. deViries
For the first time results are presented of an indirect comparison of ten national standards for air kerma for ten radiation qualities of the ISO 4037 narrow spectrum series in the range of 30 kV to 300 kV. Nine of the ten participants maintain primary air

X-Ray and Gamma-Ray Absorbed Dose Profiles in Teeth: An EPR and Modelling Study

December 31, 2007
Author(s)
S Sholom, C M. O'Brien, E Bakhanova, V Chumak, Marc F. Desrosiers, A Bouville
Dose profiles in teeth have been experimentally and theoretically studied for different energies and geometries of incident X- and gamma-rays. The experiments were conducted with teeth inside of an Alderson phantom using monodirectional radiation beams at