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Calorimetry based upon remote sensing of the temperature field in an irradiated volume would offer distinct advantages for the dosimetry of nonstandard beams
The fundamental photon and charged particle interaction data and the radiation transport methods, pioneered and developed at NIST to calculate the penetration
To compare the calibration capabilities for the spectral responsivity in the vacuum-ultraviolet spectral region between 135 nm and 250 nm, PTB and NIST agreed
This program is directed towards characterizing the birefringence properties of optical materials for the wavelength range 0.12 μm – 15 μm. The birefringence
Central to fulfilling many of the Division’s programmatic goals, and those of other divisions at NIST-Boulder, the Quantum Electromagnetics Division is
Calibrations of the The Extreme ultraviolet/X-ray Irradiance Sensor (EXIS), which will be installed on the Geostationary Operations Environment Satellite R
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 137Cs and 60Co gamma-ray beams and for absorbed
NIST calibrates certain user-owned encapsulated beta-particle sources and certain standards laboratory transfer instruments for applications in radiation
The Dosimetry Group calibrates well-type ionization chambers using Xoft miniature x-ray sources, which provide low-energy x-rays (< 50 keV) for electronic
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
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
Our research focuses on miniaturized laser sources with narrow linewidth that can operate in ambient environments. Lasers with high spectral purity can enable a
Every four years, the Committee on Data for Science and Technology (CODATA) issues recommended values of the fundamental physical constants. The values are
NIST is building a cold-atom vacuum sensor (CAVS) that will be able to measure pressures in the ultra-high vacuum (UHV) regime corresponding to pressures less
We are developing a scalable infrastructure for strontium optical-lattice clocks based on integrated photonics. This research results in new technologies to
An international measurement comparison for a 99Tc solution hosted by National Physical Laboratory (NPL) of the UK, (CCRI(II)K-2. 99Tc comparison) was completed
All of the plutonium isotopes, which have a very high biotoxicity, are man-made and result from various nuclear activities. Plutonium-241 is a very low-energy
Comparisons for the national standards of air kerma from therapy level and radiation protection gamma-ray beams were conducted by the NIST and the Bureau
We investigate collisions of atoms in either micro-Kelvin gasses or in nano-colliders, where two small atomic clouds are made to collide with adjustable energy