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arXiv · 1706.04403

Finding the number density of atomic vapor by studying its absorption profile

Harish Ravi·Mangesh Bhattarai·Vasant Natarajan
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Abstract

We demonstrate a technique for obtaining the density of atomic vapor, by doing a fit of the resonant absorption spectrum to a density-matrix model. In order to demonstrate the usefulness of the technique, we apply it to absorption in the ${\rm D_2}$ line of a Cs vapor cell at room temperature. The lineshape of the spectrum is asymmetric due to the role of open transitions. This asymmetry is explained in the model using transit-time relaxation as the atoms traverse the laser beam. We also obtain the latent heat of evaporation by studying the number density as a function of temperature close to room temperature.

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Harish Ravi, Mangesh Bhattarai, Vasant Natarajan. 2017-06-14. Finding the number density of atomic vapor by studying its absorption profile. https://arxiv.org/abs/1706.04403

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