High sensitivity microwave spectroscopy in a cryogenic buffer gas cell.

  title={High sensitivity microwave spectroscopy in a cryogenic buffer gas cell.},
  author={Jessica P. Porterfield and Lincoln Satterthwaite and Sandra Eibenberger and David Patterson and Michael C. McCarthy},
  journal={The Review of scientific instruments},
  volume={90 5},
We describe an instrument which can be used to analyze complex chemical mixtures at high resolution and high sensitivity. Molecules are collisionally cooled with helium gas at cryogenic temperatures (∼4-7 K) and subsequently detected using chirped pulse microwave spectroscopy. Here, we demonstrate three significant improvements to the apparatus relative to an earlier version: (1) extension of its operating range by more than a factor of two, from 12-18 GHz to 12-26 GHz, which allows a much… 

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