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For decades, astronomers and physicists have been trying to solve one of the deepest mysteries about the cosmos: An estimated 85% of its mass is missing.
Each year, hundreds of meteorites — rocky bodies left over from the formation of the solar system — bombard Earth, delivering minerals, metals and water to our
A picture may be worth a thousand words, but for astronomers, simply recording images of stars and galaxies isn’t enough. To measure the true size and absolute
Ultrashort mid-infrared laser pulses are used to observe fast molecular and photochemical reaction processes occurring in the condensed phase. We have developed
A common topic in energy systems is the need for in situ measurement of the mass transport of light ion species such as hydrogen or lithium. Neutron imaging has
Neutron beta-decay is the process in which a neutron is transformed into a proton, electron, and electron antineutrino. This process is well described in the
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Lizbeth Laureano-Perez, Leticia Pibida, Brian E. Zimmerman
An activity standard for 212Pb in equilibrium with its progeny was realized, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS)
Allan Treiman, Jacob LaManna, Isabella DeClue, Daniel S. Hussey, Lawrence Anovitz
The presence and distribution of hydrogen-bearing materials in meteorites are important constraints on processes in the early solar system, and the delivery of
Alline F. Myers, Shozo Takagi, Stanislav Frukhtbeyn, Laurence Chow, Veronika Szalai, Lonnie Cumberland, Ileana Pazos, Eaman Karim
Ionizing radiation-induced paramagnetic defects in calcified tissues like tooth enamel are indicators of irradiation dose. Hydroxyapatite (HA), the principal
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
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