A periodic table of the elements, displaying NIST critically-evaluated data on the atomic properties of the elements. Suitable for high-resolution color printing for desk or wall-chart display.
A National Measurement System for Radiometry, Photometry, and Pyrometry Based upon Absolute Detectors. The history of electrical substitution radiometers at NIST is briefly reviewed and the implementation of the latest generation absolute cryogenic radiometer is discussed. It is proposed that NIST customers consider adopting the suggestions made in this technical note to simplify and improve their optical radiation based calibrations.
Procedures are described, in this pedagogical monograph, for making quantum mechanical calculations of rotational energy levels and rotational line intensities in diatomic molecules.
Catalog of explicit symmetry operations for the vibrational, rotational and nuclear spin functions of methane, and the use of these operations in determining symmetry labels and selection rules.
A C++ object class library (SCATMECH) has been developed to distribute models for polarized light scattering from surfaces. It is the intent of this library to allow researchers in the light-scattering community to fully utilize the models described in several NIST publications.
This article outlines the main concepts of atomic structure, with some emphasis on terminology and notation. Atomic radiation is discussed, and updated tabulations of ionization energies for the neutral atoms and transition probabilities for persistent lines of selected neutral atoms are included.
Special issue (July-August 1996) of the Journal of Research of the National Institute of Standards and Technology dedicated to reporting recent developments in Bose-Einstein condensation and related issues such as ultracold atomic collision physics.
General and technical publications on time and frequency.
The following pages will lead the reader through an introductory description of the Hall measurement technique, covering basic principles, equipment, and recommended procedures.
This on-line Anthology is a compilation of papers on the subject of surge protection that were written and published over the period 1963-2003 in the pursuit of transients and surge protection.
A web site for computational tools that solve real problems in dimensional measurement. The Engineering Metrology Gallery, also part of the toolbox, is a web-based photo gallery on dimensional measurements.
Constants, Units, & Uncertainty
Fundamental Physical Constants
Article on CODATA values, and introduction to constants for non-experts. See also: Chart with selected values of the 2014 CODATA recommended values of the Fundamental Physical Constants - SP961 - PDF
International System of Units
Publications on SI units, usage, history, and legal rulings: