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arXiv · 1203.0189

Vacuum Pressure Measurements using a Magneto-Optical Trap

Abstract

The loading dynamics of an alkali-atom magneto-optical trap can be used as a reliable measure of vacuum pressure, with loading time T indicating a pressure less than or equal to [2x10^(-8) Torr s]/T. This relation is accurate to approximately a factor of two over wide variations in trap parameters, background gas composition, or trapped alkali species. The low-pressure limit of the method does depend on the trap parameters, but typically extends to the 10^(-10) Torr range.

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T. Arpornthip, C. A. Sackett, K. J. Hughes. 2012-03-01. Vacuum Pressure Measurements using a Magneto-Optical Trap. https://doi.org/10.1103/physreva.85.033420

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