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Ryan P. Fitzgerald (Fed)

Ryan Fitzgerald is a physicist in the NIST Radiation Physics division with a focus on development of primary standards for radionuclides for multiple applications (medical, energy, environmental, etc.). He is part of multiple collaborations exploring new and improved methods for measuring radiation and radioactive decay.

NRC Postdoc Opportunities

Projects & Collaborations

Publications

Toward a New Primary Standardization of Radionuclide Massic Activity Using Microcalorimetry and Quantitative Milligram-Scale Samples

Author(s)
Ryan P. Fitzgerald, Bradley Alpert, Dan Becker, Denis E. Bergeron, Richard Essex, Kelsey Morgan, Svetlana Nour, Galen O'Neil, Dan Schmidt, Gordon A. Shaw, Daniel Swetz, R. Michael Verkouteren, Daikang Yan
We present a new paradigm for the primary standardization of radionuclide activity per mass of solution (Bq/g). Two key enabling capabilities are 4π decay

MICROMETROLOGY IN PURSUIT OF QUANTUM RADIATION STANDARDS

Author(s)
Ryan P. Fitzgerald, Zeeshan Ahmed, Denis E. Bergeron, Nikolai Klimov, Dan Schmidt, Ronald Tosh
With the recent redefinition of the SI base units in terms of constants of nature, the race is on to maximize achievable precision by developing primary

The Next Generation of Current Measurement for Ionization Chambers

Author(s)
Ryan P. Fitzgerald, Denis E. Bergeron, Dean G. Jarrett, Neil M. Zimmerman, Carine Michotte, Hansjoerg Scherer, Stephen Giblin, Steven Judge
Re-entrant ionization chambers (ICs) are essential to radionuclide metrology and nuclear medicine for maintaining standards and measuring half-lives. Metrology

Patents

Photonic Calorimeter and Process for Performing Calorimetry

NIST Inventors
Ronald Tosh , Zeeshan Ahmed , Ryan P. Fitzgerald and Nikolai Klimov
Patent Description The invention i s a photonic device whose resonance characteristics (such as, quality factor, peak position, and free spectral range) change in a predictable way in response to the interaction of radiation with the sensor and/or its surroundings. The invention can be used in an
A list of radiation-induced materials modifications that are NIST traceable

Photonic Dosimeter and Process for Performing Dosimetry

NIST Inventors
Ronald Tosh , Zeeshan Ahmed , Ryan P. Fitzgerald and Nikolai Klimov
Patent Description Radiation-induced materials modification is ubiquitous. These applications rely on dosimetry to reliably deliver the desired amount of radiation to the right place. Currently the dosimetry standard is based on calorimetry of a large water phantom irradiated exclusively by Co-60
Created May 21, 2019, Updated March 9, 2022