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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
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
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
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.
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
Optical systems that operate at wavelengths in the ultraviolet (UV) and extreme-ultraviolet (EUV) are susceptible to degradation by a number of different
Nano and atomic scale theory of the electronic, optical and mechanical properties of ultrasmall structures, such as semiconductor quantum dots and dopants in Si
The purpose of the N42 data format is to facilitate manufacturer-independent transfer of information from radiation measurement instruments for use in homeland
The Dynamic EUV Imaging and Spectroscopy for Microelectronics program in the Spin Electronics group makes use of an ultra-fast, coherent, extreme ultraviolet