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Search Publications by: Michael G. Mitch (Fed)

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Displaying 1 - 24 of 24

Early Electroscopes at the National Bureau of Standards

May 17, 2024
Bert Coursey, Brian E. Zimmerman, Michael G. Mitch, Paul Frame
This report describes the use of five electroscopes used as national standards for radioactivity for the United States during the early 20th century. This set of instruments were used for the calibration of thousands of radium-226 sources used in medical

Dosimetric characterization of a new directional low-dose rate brachytherapy source

June 21, 2018
Michael G. Mitch, Larry A. DeWerd, Manik Aima, Clifford G. Hammer, Wesley S. Culberson
CivaTech Oncology Inc. (Durham, NC) has developed a novel low-dose rate (LDR) brachytherapy source called the CivaSheet. The source is a planar array of discrete elements (“CivaDots") which are directional in nature. This work investigates the

Supplement 2 to the 2004 update of the AAPM Task Group No. 43 1 Report: Joint recommendations by the AAPM and GEC-ESTRO

September 30, 2017
Michael G. Mitch, Mark J. Rivard, Facundo Ballester, Wayne M. Butler, Larry A. DeWerd, Geoffrey S. Ibbott, Christopher Melhus
Since publication of the 2004 update to the American Association of Physicists in Medicine (AAPM) Task Group No. 43 Report (TG-43U1) and its 2007 supplement (TG-43U1S1), several new low- energy photon-emitting brachytherapy sources have become available

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

October 6, 2014
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

The Importance of Dosimetry Standardization in Radiobiology

December 30, 2013
Marc F. Desrosiers, Larry A. DeWerd, James Deye, Patricia Lindsay, Mark K. Murphy, Michael G. Mitch, Francesca Macchiarini, Strahinja Stojadinovic, Helen Stone
Radiation dose is central too much of radiobiological research. Precision and accuracy of dose measurements and reporting of the measurement details should be sufficient to allow the work to be interpreted and repeated and to allow valid comparisons to be

A Dosimetric Uncertainty Analysis for Photon-Emitting Brachytherapy Sources: Report of the AAPM Task Group No. 138 and GEC-ESTRO

February 1, 2011
Larry A. DeWerd, Geoffrey S. Ibbott, Ali S. Meigooni, Michael G. Mitch, Mark J. Rivard, Kurt E. Stump, Bruce R. Thomadsen, Jack L. Venselaar
This report addresses uncertainties pertaining to brachytherapy source dosimetry. The ISO Guide to the Expression of Uncertainty in Measurement (GUM) and the NIST Technical Note 1297 are taken as reference standards for uncertainty formalism. Uncertainties

Treatment of Uncertainties in Radiation Dosimetry

August 18, 2009
Michael G. Mitch, Larry DeWerd, Ronaldo Minniti, J Williamson
When one perform a physical measurement or a Monte Carlo simulation and obtains a numerical result, the following questions may be asked. How accurate is the result? Is the measurement or simulation method of high quality? Can the result be meaningfully

Primary Standards for Brachytherapy Sources

June 1, 2009
Michael G. Mitch, Christopher G. Soares
The AAPM dosimetry protocol for LDR brachytherapy seeds that emit x-rays of energies ≤ 50 keV is described in the TG-43U1 report (Rivard et al. 2004). In this protocol, it is specified that the strength of such sources be expressed in terms of air-kerma

Primary Standards and Dosimetry Protocols for Brachytherapy Sources

March 20, 2009
Christopher G. Soares, G. Douyssey, Michael G. Mitch
Current primary standards for the calibration of both photon and beta particle emitting brachythrapy sources are reviewed. Methods for quality control being used as well as methods of transferring these standards to secondary laboratories and user are also

Supplement to the 2004 Update of the AAPM Task Group No. 43 Report

June 1, 2007
Mark J. Rivard, Wayne Butler, Larry A. DeWerd, Saiful M. Huq, Geoffrey S. Ibbott, Christopher Melhus, Michael G. Mitch, Ravinder Nath, J Williamson
Since publication of the 2004 update to the American Association of Physicists in Medicine (AAPM) Task Group No. 43 Report (AAPM TG-43U1), several new low-energy photon-emitting brachytherapy sources have become available. Many of these sources have