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Search Publications by: Brian E. Zimmerman (Fed)

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Displaying 1 - 25 of 144

Evaluations of the decay data of 55Fe, 55Co, 103mRh, 103Pd, 129mSn and 166Ho from the Decay Data Evaluation Project (DDEP)-2024

February 18, 2025
Author(s)
Xavier Mougeot, Philippe Cassette, Valery Chechev, Christophe Dulieu, Xiaolong Huang, Mark Kellett, Tibor Kibedi, Nikolay Kuzmenko, Sylvain Leblond, Alan Nichols, Brian Zimmerman
Since 1995, members of the Decay Data Evaluation Project (DDEP) have evaluated the decay data from different radionuclides of special interest for metrology or practical applications, e.g. nuclear medicine, monitoring and reactor shielding, etc. Since 2004

Activity measurements and calibrations for 225Ac in radioactive equilibrium with its progeny

December 9, 2024
Author(s)
Denis Bergeron, Gulakhshan Hamad, Brittany Broder, Jeffrey Cessna, Adam Pearce, Jerome LaRosa, Leticia Pibida, Brian E. Zimmerman
The massic activity of 225Ac in 0.1 mol/L HCl was measured by multiple primary methods over four consistent measurement campaigns. Results from the triple-to-double coincidence ratio (TDCR) method of liquid scintillation (LS) counting were in accord with

Early Electroscopes at the National Bureau of Standards

May 17, 2024
Author(s)
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

Activity standard and calibrations for 227Th with ingrowing progeny

April 20, 2024
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Brittany Broder, Leticia Pibida, Ryan P. Fitzgerald, Morgan DiGiorgio, Elisa Napoli, Brian E. Zimmerman
Thorium-227 was separated from its progeny and standardized for activity by the triple-to-double coincidence ratio (TDCR) method of liquid scintillation counting. Confirmatory liquid scintillation-based measurements were made using efficiency tracing with

A New Evaluation of the Decay Data for 166Ho

February 23, 2024
Author(s)
Brian E. Zimmerman
The beta emitting radionuclide 166Ho has garnered attention over the years as a potential radiolabel for therapeutic medical applications. A new decay data evaluation for 166Ho has been performed using the Decay Data Evaluation Project (DDEP) methodology

Liquid scintillation efficiencies, gamma-ray emission intensities, and half-life for Gd-153

November 9, 2023
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Gulakhshan Hamad, Lizbeth Laureano-Perez, Leticia Pibida, Brian E. Zimmerman
Gadolinium-153 was standardized for activity by live-timed anticoincidence counting and an ampoule was submitted to the international reference system (SIR). Absolute emission intensities for the main γ rays were determined with calibrated high-purity

Primary standardization of 212Pb activity by liquid scintillation counting

September 22, 2022
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Lizbeth Laureano-Perez, Leticia Pibida, Brian E. Zimmerman
An activity standard for 212Pb in equilibrium with its progeny was realized, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. A Monte Carlo-based approach to estimating uncertainties due to nuclear decay data

Calorimetry in Computed Tomography Beams

March 10, 2022
Author(s)
Heather H. Chen-Mayer, Ronald Tosh, Fred B. Bateman, Paul Bergstrom, Brian E. Zimmerman
A portable calorimeter for direct realization of absorbed dose in medical computed tomography (CT) procedures was constructed and tested in a positron emission tomography (PET) CT scanner. The calorimeter consists of two small thermistors embedded in a

Ra-224 activity, half-life, and 241 keV gamma ray absolute emission intensity: a NIST-NPL bilateral comparison

December 31, 2020
Author(s)
Denis E. Bergeron, Sean Collins, Leticia Pibida, Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Peter Ivanov, John Keightley, Elisa Napoli
The national metrology institutes for the United Kingdom and the United States have compared activity standards for 224Ra, an -particle emitter of interest as the basis for therapeutic radiopharmaceuticals. Solutions of 224RaCl2 were assayed by absolute

Primary standardization of Ra-224 activity by liquid scintillation counting

October 11, 2019
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Lizbeth Laureano-Perez, Ronald Colle, Leticia S. Pibida, Elisa Napoli
A standard for 224Ra activity has been developed, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. The standard was confirmed by efficiency tracing and 4παβ(LS)-γ(NaI(Tl)) anticoincidence counting, as well as by 4πγ

Standardization of I-124 by three liquid scintillation-based methods

August 9, 2019
Author(s)
Denis E. Bergeron, Leticia S. Pibida, Brian E. Zimmerman, Jeffrey T. Cessna, Ryan P. Fitzgerald
A solution of 124I was standardized for activity by 4πβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) counting, with confirmatory measurements by triple-to-double coincidence ratio (TDCR) and CIEMAT-NIST efficiency tracing (CNET) liquid scintillation

Standardization of 64Cu activity

May 25, 2018
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Leticia S. Pibida, Brian E. Zimmerman
The complex decay scheme that makes 64Cu promising as both an imaging and therapeutic agent in medicine also makes the absolute measurement of its activity challenging. The National Institute of Standards and Technology (NIST) has completed a primary

Activity measurements of the radionuclides 18F and 64Cu for the NIST, USA in the ongoing comparisons BIPM.RI(II)-K4.F-18 and BIPM.RI(II)-K4.Cu-64

January 1, 2018
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Leticia S. Pibida, Brian E. Zimmerman, Carine Michotte, Manuel Nonis, Andrew Fenwick, Kelly Ferreira, John Keightley
In 2016, comparisons of activity measurements of 18F and 64Cu using the Transfer Instrument of the International Reference System (SIRTI) took place at the National Institute of Standards and Technology (NIST, USA). This is the first SIRTI comparison for

Natural Uranium Radioactivity Solution Standard: SRM 4321d

December 27, 2017
Author(s)
Ronald Colle, Lizbeth Laureano-Perez, Svetlana Nour, Jerome J. LaRosa, Brian E. Zimmerman, Leticia S. Pibida, Denis E. Bergeron
A new natural uranium solution standard has been produced and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material 4321d. The standard is certified for the massic activities of 234U, 235U, and