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Title: Raman spectrometer for high precision temperature sensing of atmospheric gases

We present a highly accurate Raman spectrometer capable of measuring changes in atmospheric temperature as small as 0.75 K with high spatial and temporal resolution. The spectrometer is based on a laser diode tuned to the resonant absorption line of the85Rbisotope near 780.0 nm. A heated glass cell containing Rb atoms was used as an ultranarrowband atomic absorption notch filter with0.3cm−<#comment/>1bandwidth and optical density as high as four. This filter was placed in front of the spectrograph and blocked up to 99.99% of the elastically scattered laser light, which made it possible to resolve the pure-rotational Raman spectra of molecular atmospheric gases. The relative intensities of pure-rotational Raman transitions were then used to infer atmospheric temperature changes.

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Author(s) / Creator(s):
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Applied Optics
1559-128X; APOPAI
Page Range / eLocation ID:
Article No. 2919
Medium: X
Sponsoring Org:
National Science Foundation
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