FTMW/CVI: FOURIER TRANSFORM MICROWAVE / COHERENCE SPECTROSCOPY WITH VIRTUAL INSTRUMENTS
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Date
2001
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Publisher
Ohio State University
Abstract
Modern Fourier transform microwave (FTMW) spectroscopy, first implemented as an impulse excitation technique in a steady gas-waveguide $apparatus^{a}$, started only a quarter of a century ago. Soon after, the method was supplemented for special applications, e.g. Stark-$effect^{b}$, double $resonance^{c}$, and $2D^{d}$ spectroscopy. The subsequent implementation of the technique in a supersonic jet-resonator $apparatus^{e}$ was followed by similar developments, i.e. Stark-$effect^{f}$, double $resonance^{g}$, laser $ablation^{h}$, and $DC-discharge^{i}$. $Automation^{j}$ along with the ``coaxially oriented beam-resonator $arrangement""^{k}$ (COBRA) has greatly increased efficiency, resolution, and sensitivity of current FTMW spectrometers. We present the implementation of a complete COBRA-FTMW spectrometer featuring the capabilities given above. The entire experiment is operated, either interactivle or automatically, by a graphical user interface (GUI)-based program which is capable of waveguide and resonator applications. Developed in the C programming language, while following the concept of virtual instruments (VI), the software can co-operate with a wide variety of PCI and IEEE hardware components to build the instrument. Only one application specific logic circuit, which will also be presented, is needed.
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Author Institution: Institut f\""ur Physikalische Chemie und Elektrochemie
Author Institution: Institut f\""ur Physikalische Chemie und Elektrochemie