# Atomic density of a harmonically trapped ideal gas near Bose-Einstein transition temperature

Laser Cooling and Quantum Gas

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## Abstract.

We have studied the atomic density of a cloud confined in an isotropic harmonic trap at the vicinity of the Bose-Einstein transition temperature. We show that, for a non-interacting gas and near this temperature, the ground-state density has the same order of magnitude as the excited states density at the centre of the trap. This holds in a range of temperatures where the ground-state population is negligible compared to the total atom number. We compare the exact calculations, available in a harmonic trap, to semi-classical approximations. We show that these latter should include the ground-state contribution to be accurate.

## PACS.

03.75.Hh Static properties of condensates; thermodynamical, statistical, and structural properties 03.65.Sq Semiclassical theories and applications 05.30.Jp Boson systems## Preview

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## References

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© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006