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Metrology

Ionizing radiation metrology

News and Updates

Projects and Programs

photonic calorimeter/dosimeter

Photonic Dosimetry

Ongoing
With this effort, NIST is responding to industry needs for traceable, measurement solutions that can resolve spatial variations of absorbed dose at the level of individual components on a silicon wafer or bacteria on surgical instruments. Presently, there is only limited traceability to national
Alanine/EPR

Medical (Archive): Small-field Therapy Dosimetry Studies Using Alanine/EPR

Completed
Developments in radiotherapy have significantly increased the use of small fields in stereotactic procedures and IMRT fields composed of small fields. Ionization chambers are not always suitable where situations of high dose gradients, time-dose variance, and non-uniform beam distributions are

Radioanalytical Metrology

Ongoing
The Group engages in a wide range of methods applicable to the detection and characterization of nuclear materials. The work can benefit environmental studies, waste remediation, naturally occurring radioactivity detection and characterization and general radioanalytical metrology. Expertise in

Publications

A bilateral comparison of 227Th activity standards between NPL and NIST

Author(s)
Andrew Fenwick, Denis Bergeron, Brittany Broder, Emma Bendall, Jeffrey Cessna, Sean Collins, Leticia Pibida, Natasha Ramirez, Elisa Napoli
The National Physical Laboratory (United Kingdom) and the National Institute of Standards and Technology (United States) each determined the massic activity and

Tools and Instruments

X-ray backscatter systems

X-ray Backscatter Systems

X-ray backscatter systems are used for the screening of personnel for hidden weapons and other contraband. Unlike conventional radiographic x-ray systems