We report on a new optical implementation of primary gas thermometry based on laser-absorption spectrometry in the near infrared. The method consists in retrieving the Doppler broadening from highly accurate observations of the line shape of the R(12) (0,0,0)->(1,2,1) transition in a CO2 gas at thermodynamic equilibrium. Doppler width measurements as a function of the gas temperature, ranging between the triple point of water and the gallium melting point, allowed for a spectroscopic determination of the Boltzmann constant with a relative accuracy of about 1.6 over 10000.
Primary gas thermometry by means of laser-absorption spectroscopy: Determination of the boltzmann constant / Casa, G.; Castrillo, A.; Galzerano, G.; Wehr, R.; Merlone, A.; di Serafino, D.; Laporta, P.; Gianfrani, L.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 100:20(2008), p. 200801. [10.1103/PhysRevLett.100.200801]
Primary gas thermometry by means of laser-absorption spectroscopy: Determination of the boltzmann constant
di Serafino D.;
2008
Abstract
We report on a new optical implementation of primary gas thermometry based on laser-absorption spectrometry in the near infrared. The method consists in retrieving the Doppler broadening from highly accurate observations of the line shape of the R(12) (0,0,0)->(1,2,1) transition in a CO2 gas at thermodynamic equilibrium. Doppler width measurements as a function of the gas temperature, ranging between the triple point of water and the gallium melting point, allowed for a spectroscopic determination of the Boltzmann constant with a relative accuracy of about 1.6 over 10000.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
