dc.creator Sow, P. L. T. en_US dc.creator Merji, S. en_US dc.creator Tokunaga, S. K. en_US dc.creator Lemarchand, C. en_US dc.creator Triki, M. en_US dc.creator Borde, C. en_US dc.creator Chardonnet, C. en_US dc.creator Darquie, B. en_US dc.creator Daussy, C. en_US dc.date.accessioned 2013-07-16T21:44:24Z dc.date.available 2013-07-16T21:44:24Z dc.date.issued 2013 en_US dc.identifier 2013-FD-16 en_US dc.identifier.uri http://hdl.handle.net/1811/55503 dc.description Author Institution: Laboratoire de Physique des Lasers, Universite Paris 13, Sorbonne Paris Cite, CNRS, F-93430, Villetaneuse, France en_US dc.description.abstract Accurate molecular spectroscopy in the mid-infrared region allows precision measurements of fundamental constants. For instance, measuring the linewidth of an isolated Doppler-broadened absorption line of ammonia around 10 $\mu$m enables a determination of the Boltzmann constant $k_{\mathrm{B}}$, 073028 (2011).}. We report on our latest measurements. The main systematic effects, including the temperature control, will be discussed and an error budget will be presented in which the global uncertainty on systematic effects is at the level of a few ppm. This is valid provided that data is recorded under the optimized experimental conditions determined by the studies of systematic effects and provided that spectra are fitted to the speed-dependent Voigt profile, identified as the most suitable lineshape for our measurements , 062510 (2012).}. A determination of $k_{\mathrm{B}}$ by Doppler spectroscopy with a combined uncertainty of a few ppm is within reach. This is comparable to the best current uncertainty obtained using acoustic methods and would make a significant contribution to any new value of $k_{\mathrm{B}}$ determined by the CODATA. Furthermore, having multiple independent measurements at these accuracies opens the possibility of defining the Kelvin by fixing $k_{\mathrm{B}}$, an exciting prospect considering the upcoming redefinition of the International System of Units (SI). en_US dc.language.iso en en_US dc.publisher Ohio State University en_US dc.title ACCURATE DETERMINATION OF THE BOLTZMANN CONSTANT BY DOPPLER SPECTROSCOPY TOWARDS A NEW DEFINITION OF THE KELVIN en_US dc.type Article en_US
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