corner
corner
APS » Journals » Phys. Rev. Lett. » Volume 98 » Issue 25
< Previous Article | Next Article >

Phys. Rev. Lett. 98, 250801 (2007) [4 pages]

Direct Determination of the Boltzmann Constant by an Optical Method

Download: PDF (226 kB) Buy this article Export: BibTeX or EndNote (RIS)

C. Daussy, M. Guinet, A. Amy-Klein, K. Djerroud, Y. Hermier*, S. Briaudeau*, Ch. J. Bordé, and C. Chardonnet
Laboratoire de Physique des Lasers, UMR CNRS 7538, Institut Galilée, Université Paris 13, 99, avenue J.-B. Clément, 93430 Villetaneuse, France

Received 21 January 2007; published 18 June 2007

We have recorded the Doppler profile of a well-isolated rovibrational line in the ν2 band of 14NH3. Ammonia gas was placed in an absorption cell thermalized by a water-ice bath. By extrapolating to zero pressure, we have deduced the Doppler width which gives a first measurement of the Boltzmann constant kB by laser spectroscopy. A relative uncertainty of 2×10-4 has been obtained. The present determination should be significantly improved in the near future and contribute to a new definition of the kelvin.

© 2007 The American Physical Society

URL:
http://link.aps.org/doi/10.1103/PhysRevLett.98.250801
DOI:
10.1103/PhysRevLett.98.250801
PACS:
06.20.Jr, 33.20.Ea, 42.62.Fi

*Permanent address: Institut National de Métrologie LNE-INM-CNAM, La Plaine Saint-Denis, France.

 
< Previous Article | Next Article >