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Ultraviolet Radiation Group

Maintains, improves, and disseminates our National standards for ultraviolet (UV) and extreme-ultraviolet (EUV) radiometry.

The group’s mission is to maintain, improve, and disseminate the National standards for ultraviolet (UV) and extreme-ultraviolet (EUV) radiometry through the use of the Synchrotron Ultraviolet Radiation Facility - SURF III. SURF III provides an absolute scale of continuum radiation from the soft x-ray to the infrared spectral regions, with ideal output profile for EUV studies related to solar physics and the development of EUV lithography. SURF III produces calculable irradiance traceable to the SI units to less than 1 % absolute uncertainty from 4 nm to 400 nm. There are several beamlines equipped for radiometer, spectroradiometer, and lamp calibrations; reflectometry and transmission measurements; and degradation and lifetime studies.

Calibration Services


The Ultraviolet Radiation Group welcomes opportunities to collaborate on joint research, technology, and standards development projects to advance the measurement of ultraviolet (UV) and extreme ultraviolet (EUV) sources, detector, and material properties. The group provides multiple opportunities for students, scientists, industry, academia, and other R&D laboratories to collaborate. Specific opportunities depend on current areas of interest within the Group, but may include undergraduate research fellowship, postdoctoral fellowships, visiting scientist, and guest researchers as well as various cooperative research arrangements ranging from formal agreements, such as CRADA, Consortia, and interagency agreements, to informal collaborations. For more details, see Employment and Internship Opportunities and Collaboration Opportunities.

Projects and Programs

Tools and Instruments

News and Updates

Spotlight: SURF and Solar Storms

When the surface of the Sun erupts, it emits dangerous particles that can knock out GPS and communication links on our planet, but the rain of particles from a

EUV Calibrations for Satellite Sensors

Thanks to precision calibration measurements recently performed at NIST, satellites may soon be looking at sunlight with new and improved vision. On July 22


Silicone tube humidity generator

Robert F. Berg, ,
We describe the model and construction of a two-flow (or divided-flow) humidity generator, developed at LNE-CNAM, that uses mass flow controllers to mix a



Acting Group Leader

Office Manager