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Synchrotron Ultraviolet Radiation Facility

The NIST Synchrotron Ultraviolet Radiation Facility-III (SURF-III) is a third-generation electron “storage ring,” so named because electrons circulate in it for periods up to several days. As the electrons build up their velocity around the ring, the magnetic fields that guide them also increase their strength, resulting in a circular beam of electrons that travel in a loop of fixed size. As they move, these electrons release electromagnetic radiation that then travels along “beamlines” to experimental stations. These photon beamlines are used to calibrate light-detection sensors and how materials interact with light. They can also help calibrate satellite instrumentation used to monitor space weather and advance techniques for creating tiny devices for next-generation computer chips. 

Diagram of SURF machinery on blue background
Schematic drawing of the NIST synchrotron, 1967
Credit: NIST

The first machine was installed at the old National Bureau of Standards (NBS, now the National Institute of Standards and Technology, or NIST) site in Washington, D.C.

Overhead view of circular machinery
Electron storage ring for the SURF synchrotron being installed in Building 245 in 1966
Credit: NIST

Significant upgrades to the facility were carried out in 1961, when it was moved to Building 245 on the new campus in Gaithersburg, Maryland. Additional upgrades occurred in 1974 and 1999. 

A man adjusts a fitting on a metal pipe
Robert Madden, NIST physicist, with SURF-II in 1980s
Credit: NIST

Nine beamlines are presently available to users from NIST and outside institutions. 

Overhead view of scientists standing among linear devices in a lab
Overhead view of the NIST Synchrotron Ultraviolet Radiation Facility (SURF)
Credit: NIST

The continuous radiation from SURF-III is used as a national standard of spectral irradiance for industrial applications and fundamental research alike. 

Person in a clean suit places a detector package in a scientific instrument
The SURF Beam Line 2 provides the state-of-the art calibration for sensors used on satellites for solar physics and atmospheric monitoring  in the range from 2 nm to 400 nm. In this photo, a student from University of Colorado is placing the detector package for calibration in the beam line for an Extreme Ultraviolet Variability Experiment for NASA’s Solar Dynamics Observatory Mission.


Credit: NIST
Created July 29, 2019, Updated September 20, 2019