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Physical Measurement Laboratory /Radiation Physics Division

Dosimetry Group

The Dosimetry Group advances the measurement of quantities important in the radiological sciences through programs in the dosimetry of x-rays, gamma-rays, electrons, and other charged particles.

Ron Tosh

Calibrating Cancer Radiotherapy Beams Using Light and Sound
chamber and computer simulation

Computing for Better Radiation Therapy

The Dosimetry Group develops, maintains, and disseminates the national standards for the gray, the Système International (SI) unit for radiation dose, for medical, radiation processing, homeland security, and radiation protection applications.

News and Updates

chamber and computer simulation

Computing for Better Radiation Therapy

Doctors devising a plan of attack on a tumor may one day gain another tactical advantage thanks to a series of sophisticated calculations proposed by PML's...

Projects and Programs

Accelerator Facilities

Ongoing
The Division's accelerator facilities continue to support a broad range of research efforts in the areas of industrial and medical dosimetry, homeland security, radiation-hardness testing and materials-effects studies. Topics of research during this reporting period included: (1) a broad-energy...
spectrometer images

Basic Metrology: Applications of Diagnostic X-ray Spectrometers

Ongoing
These have been fielded to help characterize the performance and x-ray spectra from advanced medical x-ray sources, laser-produced plasmas, terawatt pulsed accelerators, electron cyclotron resonance ion sources, electron-beam ion traps, intense ultrafast laser sources, and inverse-Compton...

Basic Metrology: Dose/Dose-Rate Effects in Alanine Dosimetry

Ongoing
Check standards are used by the NIST Radiation Physics Division to monitor the performance of the alanine dosimetry system which is central to its high-dose transfer dosimetry service. These measurements are performed to confirm the operational readiness of the calibration curve. Deviations from the...

Basic Metrology: High-Dose Dosimetry Uncertainty Tables

Ongoing
Gammacell™ Calibration Geometry Dose Rate Uncertainty Source Type A (%) Type B (%) Water Calorimetry in Vertical Beam 0.16 0.51 Gammacell/Pool Source Ratio Data 0.10 Pool/B036 Source Ratio Data 0.17 Geometry Correction Factor 0.11 Field Uniformity 0.01 Source Timer (irrad time > 8min) 0.20 Co-60...

Publications

Calorimetry in Computed Tomography Beams

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...

Awards

Jack Glover Receives 1906 Award

In recognition for his effective leadership of SC 45B/WG 17, as well as his role as project leader of IEC 62463:2024, Radiation protection instrumentation — X-ray systems for the security screening of persons.

Contacts

Group Leader

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