MicroWave Spectroscopy Laboratory
















Instruments RAD Spectrometer

Spectrometer with frequency synthesizer and radio acoustical detection of absorption (RAD Spectrometer)

The spectrometer features:

  • Coherent radiation source with precision frequency control
  • Acoustical detection of absorption
  • Amplitude modulation & 1F Lock-in amplification
  • Line shape processing software
  • Pressure range: optimal 0.1 10 Torr usable 0.01 100 Torr
  • Frequency range: 35 1500 GHz
  • Typical absorption sensitivity (at time constant 1s.) ~ 10-8 cm-1
  • Studied gas temperature range from -35C up to +75C

Detailed description of RAD spectrometer

Example of recording demonstrating RAD spectrometer sensitivity.

Example of application of simplest version of RAD spectrometer (without frequency synthesizer) for broad-band high resolution spectroscopy.

Example of lineshape, line broadening and line shifting studies with BWO based submillimeter-wave frequency synthesizer with RAD gas cell.

Example of line broadening parameter measurements accuracy achieved by RAD spectrometer.

Demonstration of minimization of systematical errors

Example of broadband study of molecular spectrum using submillimeter frequency synthesizer and RAD gas cell - Teraherz spectrum of oxygen.

Example of temperature dependence study - Collisional broadening of O2 lines.

Teraherz spectrum of OCS.


   Institute of Applied Physics of the Russian Academy of Sciences
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