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Shine a flashlight into murky pond water and the beam won’t penetrate very far. Absorption and scattering rapidly diminishes the intensity of the light beam
Jeffrey Herrera is one of NIST’s health physicists, ensuring our ability to safely use radioactive materials for research and supporting radiation safety
For some 30 years, scientists have used superconducting materials to record the tiniest specks of light imaginable — individual photons, or single particles of
Ultrashort mid-infrared laser pulses are used to observe fast molecular and photochemical reaction processes occurring in the condensed phase. We have developed
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
Precise calibration of short-lived radioactive material is essential for nuclear medicine and power plant applications. To deliver such calibrations on-demand
Dianne L. Poster, C Cameron Miller, Yaw S. Obeng, John J. Kasianowicz, Michael T. Postek, Norman Horn, Troy Cowan, Richard Martinello
The development of an international, precompetitive, collaborative, ultraviolet (UV) research consortium is discussed as an opportunity to lay the groundwork
Huaiyu 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
Denis E. Bergeron, Karsten Kossert, Sean Collins, Andrew Fenwick
Interest in targeted cancer therapy with alpha-emitting radionuclides is growing. To evaluate emerging radiotherapeutic agents requires precise activity
Three independent femtosecond laser systems used for generating ultrafast pulses in the mid-IR (and far infrared:THz) through the UV; infrared (InSb and MCT)
Absolute source-based radiometry is founded in the traceability of a light source’s output to measurable operational parameters. The absolute irradiance at BL-2
Radioactivity measurements for diagnostic and therapeutic nuclear medicine in the United States are based on measurements at NIST. Activity measurements for the
The Neutron Interferometry and Optics Facilities are located at the NIST Center for Neutron Research. They are one of the world's premier facilities for neutron