Title :
The determinations of the Boltzmann constant
Author_Institution :
INM/CNAM, LNE, La plaine Saint Denis
Abstract :
The international community started recently to look for a new way to define the Kelvin. Different experiments around the world have begun. This presentation will describe very briefly the four different techniques currently used for the redetermination of k, namely the measurement of the speed of sound in pure helium-4, the determination deduce of the Doppler profile of the linear absorption line, the measurement of the noise power in an electrical resistance and finally the change of refractive index in function of the density of pure helium-4.
Keywords :
Doppler broadening; acoustic measurement; constants; electric noise measurement; helium; refractive index; temperature measurement; units (measurement); Boltzmann constant; Doppler profile; He; Kelvin; density function; electrical resistance; linear absorption line; noise power measurement; pure helium-4; refractive index; sound speed measurement; Absorption; Acoustic noise; Current measurement; Density measurement; Electric variables measurement; Electrical resistance measurement; Kelvin; Noise measurement; Power measurement; Velocity measurement;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 2008. CPEM 2008. Conference on
Conference_Location :
Broomfield, CO
Print_ISBN :
978-1-4244-2399-6
Electronic_ISBN :
978-1-4244-2400-9
DOI :
10.1109/CPEM.2008.4574771
