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Updated: Jun 15, 2026
09:53
Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation
Published on: October 30, 2012
Photoelectric scanning (6.65-m) spectrometer for VUV cross-section measurements
Applied Optics
|March 11, 2010
Summary
A new photoelectric scanner for a vacuum spectrograph achieves 0.001 nm wavelength resolution, surpassing existing vacuum monochromators. This advancement enables detailed analysis of molecular spectra in the vacuum ultraviolet region.
Area of Science:
- Spectroscopy
- Atomic and Molecular Physics
- Physical Chemistry
Background:
- Traditional plate holders in vacuum spectrographs limit real-time spectral analysis.
- Existing vacuum monochromators have limitations in wavelength resolution.
Purpose of the Study:
- To introduce a novel photoelectric scanner for a 6.65-m normal incidence vacuum spectrograph.
- To achieve superior wavelength resolution for vacuum ultraviolet spectroscopy.
Main Methods:
- Integration of a photoelectric detector and a mechanically scanning exit slit into a vacuum spectrograph.
- The grating and entrance slit remain stationary during spectral scanning.
- Operation in the 120-300 nm wavelength region.
Main Results:
- The developed scanning spectrometer achieves a wavelength resolution of 0.001 nm.
- This resolution is superior to that of any currently available vacuum monochromator.
- Demonstrated performance through vacuum ultraviolet scans of CO and O(2) bands.
Conclusions:
- The photoelectric scanner significantly enhances the capabilities of vacuum spectrographs.
- The instrument provides unprecedented resolution for studying molecular spectra.
- Enables detailed analysis of emission and absorption spectra in the vacuum ultraviolet.
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