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Primary activity standards for radionuclides form the foundation for the many products and services of the Radioactivity Group and serve as ground-truth for
Calorimetry based upon remote sensing of the temperature field in an irradiated volume would offer distinct advantages for the dosimetry of nonstandard beams
NIST is in its eighth decade of providing critically evaluated, comprehensive databases of cross-section information for ionizing photons (x and gamma rays)
The fundamental photon and charged particle interaction data and the radiation transport methods, pioneered and developed at NIST to calculate the penetration
Expanding applications of radioactivity in medicine, energy, and national security demand quantification of complex radionuclide mixtures at uncertainty levels
Three dosimetry calibration laboratories accredited by the American Association of Physicists in Medicine (AAPM) routinely perform calibrations of a large
The Dosimetry Group maintains and disseminates the national measurement standards for air-kerma (exposure) from 137 Cs and 60 Co gamma-ray beams and for
NIST calibrates certain user-owned encapsulated beta-particle sources and certain standards laboratory transfer instruments for applications in radiation
Small radioactive "seed" sources used in prostate brachytherapy, containing the radionuclides 103 Pd, 125 I, or 131 Cs, are calibrated in terms of air-kerma
The Dosimetry Group calibrates well-type ionization chambers using Xoft miniature x-ray sources, which provide low-energy x-rays (< 50 keV) for electronic
The new NIST x-ray calibration facility has been designed to improve the measurement conditions for x-ray scatter, motion control, environmental conditions
Proficiency tests have been offered by the Dosimetry Group to support air-kerma traceability since the 1980’s. The Quality Management System incorporates the
NIST maintains the Californium Neutron irradiation Facility (CNIF), which is an exposure facility providing fast neutrons for irradiations requiring high
Precise calibration of short-lived radioactive material is essential for nuclear medicine and power plant applications. To deliver such calibrations on-demand
NIST provides the national reference for the calibration of neutron radiation detectors used for personnel protection and for neutron personnel dosimeters.
The neutron source calibration facility operated by NIST is a world-class calibration laboratory providing neutron source calibration services for radioisotopic
A second Manganese Sulfate Bath is in service. It is smaller than our large bath and it is portable. The former feature allows it to measure the emission rate
The Standard Reference Materials Program of the National Institute of Standards and Technology (NIST) provides science, industry, and government with a central
Absorbed dose is the energy imparted per unit mass by radiation to an irradiated target. The SI unit of absorbed dose is the gray (abbreviated Gy), equivalent
NIST participated in an international comparison of standards for absorbed dose to water for 60 Co gamma radiation at radiation-processing dose levels organized
An international measurement comparison for a 99 Tc solution hosted by National Physical Laboratory (NPL) of the UK, (CCRI(II)K-2. 99 Tc comparison) was
Certified Reference Materials (CRMs) are needed to develop and validate method analysis, and also for quality monitoring of established radioanalytical