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arXiv · 1308.2105

Absolute density measurement of SD radicals in a supersonic jet at the quantum-noise limit

Arin Mizouri·Lianzhong Deng·Jack S. Eardley·N. Hendrik Nahler·Eckart Wrede·David Carty
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Abstract

The absolute density of SD radicals in a supersonic jet has been measured down to $(1.1\pm0.1)\times10^5$ cm$^{-3}$ in a modestly specified apparatus that uses a cross-correlated combination of cavity ring-down and laser-induced fluorescence detection. Such a density corresponds to $215\pm21$ molecules in the probe volume at any given time. The minimum detectable absorption coefficient was quantum-noise-limited and measured to be $(7.9\pm0.6)\times10^{-11}$ cm$^{-1}$, in 200 s of acquisition time, corresponding to a noise-equivalent absorption sensitivity for the apparatus of $(1.6\pm0.1)\times10^{-9}$ cm$^{-1}$ Hz$^{-1/2}$.

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Arin Mizouri, Lianzhong Deng, Jack S. Eardley, N. Hendrik Nahler, Eckart Wrede, David Carty. 2013-08-09. Absolute density measurement of SD radicals in a supersonic jet at the quantum-noise limit. https://doi.org/10.1039/c3cp53394h

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