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Csilla Szabo-Foster (Fed)


Csilla Szabo-Foster is a physicist in the Dosimetry group of the Radiation Physics Division at the National Institute of Standards and Technology (NIST). She is responsible for dosimetry calibration services for low dose rate (LDR) brachytherapy seeds and for protection level beta emitting sources and their measurement devices. With more than 20 years of experience in X-ray physics, she is excited to use spectroscopic methods in modern dosimetry. Before this role, she used high-resolution X-ray spectroscopy to perform tests of Quantum Electrodynamics (QED) theories of highly charged ions at the Laboratoire Kastler Brossel in Paris and the Naval Research Laboratory (NRL) in Washington, DC. From 2015 to 2020, she led the modernization of NIST's Vacuum Double Crystal Spectrometer (VDCS) lab. Dr Szabo-Foster believes that rigorous measurement setup and precision in her calibrations will provide reliable results that will benefit the medical physics community and the greater public.

Dr Szabo-Foster led the modernization of the protection level beta calibration service, resulting in a successful campaign for the EURAMET international comparison in 2022. She is currently working on upgrading the data acquisition system of the brachytherapy source calibration facility at NIST.

Dr Szabo-Foster is a member of the American Association of Physicists in Medicine (AAPM) and holds a voting appointment at the Calibration Laboratory Accreditation Subcommittee (CLA). Csilla holds a PhD degree in Physics from the University of Debrecen, Hungary. Additionally, she is a member of the American Physical Society (APS).

When she is not thinking about dosimetry and physics, Csilla enjoys spending time with her husband, two children, and their two cats or planning exciting trips, including nature hikes.

Calibration Services


  • 2000 Fulbright Fellowship
  • 2015 NIST grant
  • 2020 Distinguished Associate Award


The NIST Silicon Lattice Comparator Upgrade

Marcus Mendenhall, James Cline, Csilla Szabo-Foster, Albert Henins
The NIST Silicon lattice comparator has ben in service in various forms since the 1970s. It is capable of measuring the difference in lattice spacing between

Absolute energies and emission line shapes of the x-ray lines of lanthanide metals

Joseph Fowler, Galen O'Neil, Bradley K. Alpert, Douglas Bennett, Edward V. Denison, William Doriese, Gene Hilton, Lawrence T. Hudson, Young I. Joe, Kelsey Morgan, Daniel Schmidt, Daniel Swetz, Csilla I. Szabo-Foster, Joel Ullom
We use an array of transition-edge sensors, cryogenic microcalorimeters with 4 eV energy resolution, to measure the x-ray emission-line profiles of four
Created September 19, 2019, Updated April 2, 2024