Title :
Proposed pressure standard based on capacitance measurements
Author_Institution :
Div. of Phys. & Chem. Properties, Nat. Inst. of Stand. & Technol., Gaithersburg, MD, USA
Abstract :
We propose to measure the dielectric constant /spl epsiv/ and the thermodynamic temperature T of helium near 273.16 K and to calculate the pressure p(/spl epsiv/,T) of the helium from the fundamental constants, quantum mechanics, and statistical mechanics. If the molar polarizability of helium A/sub /spl epsiv// is calculated more accurately, the proposed pressure standard might attain relative standard uncertainty of 6/spl times/10/sup -6/ for pressures near 1 MPa, a result of considerable interest to pressure metrology.
Keywords :
capacitance measurement; density; equations of state; helium; measurement standards; permittivity; polarisability; pressure measurement; 1 MPa; 273.16 K; He; bridges; capacitance measurement; density; dielectric constant; fundamental constants; molar gas constant; molar polarizability; pressure metrology; pressure standard; quantum mechanics; relative standard uncertainty; stable capacitors; statistical mechanics; thermodynamic temperature; virial equation of state; Capacitance measurement; Dielectric constant; Dielectric measurements; Helium; Measurement standards; Mechanical variables measurement; Pressure measurement; Quantum mechanics; Temperature distribution; Thermodynamics;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 1998 Conference on
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-5018-9
DOI :
10.1109/CPEM.1998.699811
