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Ryan P. Fitzgerald

Ryan Fitzgerald is a physicist working in the field of Ionizing Radiation, creating primary standards for radionuclides and researching new and improved methods for measuring radiation and quantifying radioactive material. Dr. Fitzgerald has published dozens of papers on nuclear physics, radiation detection, and primary standards for radioactivity. He has collaborated on radioactivity applications with others at NIST that have positive impact across numerous fields of science and society, including medicine, energy, safety, and security. One long-term interest is in developing computer simulations of radiation detection instruments to improve performance and decrease uncertainty in measurement. His latest interests are in applying new technologies to radiation physics, including developing cryogenic spectrometers for characterizing radioactive decay, and radiation sensors based on photonic resonators.

Projects & Collaborations


The Next Generation of Current Measurement for Ionization Chambers

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

Ohms Law Low-current Calibration System for Ionization Chambers

Dean G. Jarrett, Shamith U. Payagala, Ryan P. Fitzgerald, Denis E. Bergeron, Jeffrey T. Cessna, Charles J. Waduwarage Perera, Neil M. Zimmerman
A system for the calibration of electrometers that measure currents from ionization chambers is described. The calibration system uses a 1 GΩ standard resistor
Created May 21, 2019