Accurate atomic data for neutral atoms and ions are required in support of high-technology products and manufacturing processes as well as advanced scientific applications. The primary source of such data is high-resolution optical spectroscopy. Spectrometers in NIST's High-Resolution Ultraviolet and Optical Spectroscopy Facility are the most powerful in the world for observations of emission and absorption spectra in the soft X-ray to near infrared regions. The 10.7 m grazing-incidence and normal-incidence vacuum spectrographs permit observations from 3 nm to 600 nm with resolving powers of 70,000 to 400,000 and wavelength uncertainties as low as 0.0002 nm. In the visible and near-infrared region, an echelle spectrograph provides resolving powers exceeding 1,000,000. NIST's new high-resolution Fourier transform spectrometer will be capable of observations from 200 nm to 18 µm with unmatched resolution and wavelength accuracy. A variety of discharge sources are used to excite spectra of neutral atoms and ions stripped of up to 20 electrons. Species up to 40 times ionized are observed in plasmas created by ablating samples with a high-power laser. Current NIST research includes development of wavelength standards used for calibration of the high-resolution spectrograph on the Hubble Space Telescope, observations of transitions in highly ionized atoms for plasma diagnostics in tokamaks, development of a promising new scheme for an extreme ultraviolet laser, and precise isotope shifts of mercury wavelengths needed to interpret ultraviolet spectra of stars.

Contact: Joseph C. Reader
Atomic Physics Division