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Atomic Spectroscopy Group

The mission of the Atomic Spectroscopy Group is to measure, calculate, critically compile, and disseminate reference data on atomic properties and fundamental constants in support of basic research, commercial development, and national priorities.

The program in atomic spectroscopy at NIST provides accurate reference data on spectral lines and energy levels for a wide variety of important applications. Our spectrometers, among the most powerful of their type in the world, can record spectra from the hard x-ray (wavelength < 0.1 nm) to the infrared (wavelength = 18 000 nm) and include a 10.7 m normal-incidence spectrograph, a 10.7 m grazing incidence spectrograph, a high resolution Fourier transform spectrometer, a high accuracy Fabry-Pérot laser wavemeter, a grazing incidence extreme-ultraviolet spectrometer, and a transition-edge-sensor microcalorimeter. The Data Center compiles wavelengths, energy levels, and transition probabilities that support numerous applications in industry and the scientific community.

The Atomic Spectroscopy Group at NIST has a long history of contributions to optical science and metrology. Please read Joseph Reader's report on the group's history for more information.

Taking Measure: Just a Standard Blog

Isabelle Rivera poses smiling at a computer with two monitors, one showing a spreadsheet and the other multiple file icons.
NIST summer intern Isabelle Rivera
Credit: M. King/NIST

Reaching for the Stars: My Summer Internship Learning About Spectroscopy in Space and on Earth. As a summer high school intern at NIST, I got to take a deep dive into one of the ways scientists study space — the absorption and emission of light by matter, known as spectroscopy.

Photo of purplish black sky with a streak of bright lightning
Credit: Y. Ralchenko/NIST

In Pursuit of Plasma Power: Hot Stuff, Snowstorms, and Starry Skies. Do we really need hot stuff? I’m not talking about Donna Summer’s disco hit of 1979 or global warming. I’m not talking about anything so lukewarm as the surface of our sun—a mere 6,000 kelvins. I don’t even mean something as hot as 1,000,000 kelvins. No, the kind of hot stuff I’m talking about is closer to an unimaginable 200,000,000 kelvins! What possible use could we have for something so hot?

News and Updates

Spotlight: Gillian Nave and Jacob Ward

STEM is STELLAR! In November 2019, NIST’s Gillian Nave and Jacob Ward brought celebrations of Mercury’s transit (the point where Mercury passes between the

Projects and Programs

Atomic Spectroscopy Data Center

Critical compilations of atomic energy levels, transition wavelengths, and transition probabilities. Online databases.

High Resolution Atomic Spectroscopy

Accurate measurements of atomic wavelengths, energy levels, oscillator strengths and isotope and hyperfine structure using diffraction grating spectrographs


A new publication describes METIS, a Metrology Exchange to Innovate in Semiconductors We are seeking comments on the draft publication through February 16, 2024


Background and blended spectral line reduction in precision spectroscopy of EUV and x-ray transitions in highly charged ions

Yuri Ralchenko, Joseph N. Tan, Aung S. Naing, Galen O'Neil, Paul Szypryt, Dipti Dipti, Grant Mondeel, Roshani Silwal, Alain Lapierre, Steven Blundell, Gerald Gwinner, Antonio Camargo Villari, Endre Takacs
We report a method in EBIT spectral analysis that reduces signal from contaminant lines of 1 known or unknown origin. We utilize similar ion charge


2015 French Award

The Judson C. French Award, first presented in 2000, is granted for significant improvement in products delivered directly to industry

2009 APS Fellow - Yuri Ralchenko

For significant contributions to the relativistic theory of highly-charged ions and collisional-radiative modeling, and through creation of


Group Leader