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Physics

Radiation

News and Updates

Projects and Programs

Calibration Services: High-Dose Dosimetry

Ongoing
NIST developed the alanine dosimetry system in the early 1990's to replace radiochromic dye film dosimeters. Later in the decade the alanine system was firmly established as a transfer service for high-dose radiation dosimetry and an integral part of the internal calibration scheme supporting these

Publications

Early Electroscopes at the National Bureau of Standards

Author(s)
Bert Coursey, Brian E. Zimmerman, Michael G. Mitch, Paul Frame
This report describes the use of five electroscopes used as national standards for radioactivity for the United States during the early 20th century. This set

Benford's law in atomic spectra and opacity databases

Author(s)
Yuri Ralchenko, Jean-Christophe Pain
The intriguing law of anomalous numbers, also named Benford's law, states that the significant digits of data follow a logarithmic distribution favoring the

Activity standard and calibrations for 227Th with ingrowing progeny

Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Brittany Broder, Leticia Pibida, Ryan P. Fitzgerald, Morgan DiGiorgio, Elisa Napoli, Brian E. Zimmerman
Thorium-227 was separated from its progeny and standardized for activity by the triple-to-double coincidence ratio (TDCR) method of liquid scintillation

Tools and Instruments

Awards