NIST logo

Publications Portal

You searched on: Author: weston tew

Displaying records 11 to 20 of 52 records.
Resort by: Date / Title

11. Recent Progress in Noise Thermometry at 505 K and 693 K Using Quantized Voltage Noise Ratio Spectra
Published: 9/6/2010
Authors: Weston Leo Tew, Paul David Dresselhaus, Kevin J Coakley, H Rogalla, D. R White, J Labenski
Abstract: We report on technical advances and new results in noise thermometry at temperatures near the tin freezing point and the zinc freezing point using a Quantized Voltage Noise Source (QVNS). The temperatures are derived in a series of separate measureme ...

12. Electronic Measurement of the Boltzmann Constant with a Quantum-Voltage-Calibrated Johnson-Noise Thermometer
Published: 11/22/2009
Authors: Samuel Paul Benz, D. R White, Jifeng Qu, Horst Rogalla, Weston Leo Tew
Abstract: Currently, the CODATA value of the Boltzmann constant is dominated by a single gas-based-thermometry measurement with a relative uncertainty of 1.8 ձ0^-6. This paper describes an electronic approach to measuring the Boltzmann constant that comp ...

13. Improvements in the NIST Johnson Noise Thermometry System
Published: 4/1/2009
Authors: Samuel Paul Benz, Jifeng Qu, Horst Rogalla, D. R White, Paul David Dresselhaus, Weston Leo Tew, Sae Woo Nam
Abstract: We have developed a Johnson noise thermometry (JNT) system that is calibrated by precision waveforms synthesized with a quantized voltage noise source (QVNS). Significant improvements to the QVNS and the cross-correlation measurement electronics have ...

14. Measurement Time and Statistics for a Noise Thermometer With a Synthetic-Noise Reference
Published: 8/1/2008
Authors: D. R White, Samuel Paul Benz, J Labenski, Sae Woo Nam, Jifeng Qu, H Rogalla, Weston Leo Tew
Abstract: This paper describes methods for reducing the statistical uncertainty in measurements made by noise thermometers using digital cross correlators, and in particular, for thermometers using pseudorandom noise for the reference signal. First, a discrete ...

15. Adjustments to the NIST Realization of the ITS-90 from 5 K to 24.5561 K
Published: 5/1/2008
Authors: Weston Leo Tew, Christopher W Meyer
Abstract: Recent clarifications issued by the Consultative Committee on Thermometry (CCT) for the definitions of the equilibrium hydrogen (e-H2) triple points (TPs) and vapor-pressure points (VPs) have resulted in adjustments to the NIST-disseminated ITS-90 (T ...

16. Estimating the Triple Point Isotope Effect and the Corresponding Uncertainties for Cryogenic Fixed Points
Published: 2/1/2008
Author: Weston Leo Tew
Abstract: The estimation of sensitivities of melting temperatures due to isotopic variations in monatomic and diatomic atmospheric gases is developed from both theoretical and semi-empirical standpoints. The state of what is currently known regarding vapor pre ...

17. A Determination of the Ratio of the Zinc Freezing Point to the Tin Freezing Point by Noise Thermometry
Published: 9/12/2007
Authors: Weston Leo Tew, John Labenski, Samuel Paul Benz, Sae Woo Nam, Paul David Dresselhaus
Abstract: We have used a Johnson-Noise Thermometer (JNT) with a Quantized Voltage Noise Source (QVNS) as a calculable reference to determine the ratio of temperatures near the Zn freezing point to those near the Sn freezing point. The temperatures are derived ...

18. Resistance-Based Scaling of LF-and MF-Band Thermal Noise Powers
Published: 4/1/2007
Authors: John Labenski, Weston Leo Tew, Sae Woo Nam, Samuel Paul Benz, Paul David Dresselhaus, Charles J Burroughs
Abstract: A conventional technique for scaling thermal noise power in Johnson Noise Thermometry (JNT) is via resistance ratios. We describe measurements in the low to medium frequency (LF/MF) bands using this approach via correlation methods in the frequency d ...

19. ITS-90 Non-Uniqueness From PRT Subrange Inconsistencies Over the Range 24.56 K to 273.16 K
Published: 9/1/2006
Authors: Christopher W Meyer, Weston Leo Tew
Abstract: Calculations have been performed to study ITS-90 non-uniqueness over the range 24.5561 K to 273.16 K, where the scale is defined by an interpolating platinum resistance thermometer (PRT) that is calibrated via sets of defined fixed points. Over this ...

20. Acoustic Thermometry: New Results From 273 K to 77 K and Progress Towards 4 K
Published: 1/1/2006
Authors: Laurent Pitre, Michael R Moldover, Weston Leo Tew
Abstract: We used a quasi-spherical cavity as an acoustic and microwave resonator to measure the thermodynamic temperatures T of the triple points of mercury, argon, neon, and equilibrium hydrogen, and to measure the difference T - T90, in the range 7 K to 273 ...

Search NIST-wide:

(Search abstract and keywords)

Last Name:
First Name:

Special Publications:

Looking for a NIST Special Publication (NIST SP Series)? Place the series number and dash in the report number field (Example: 800-) and begin your search.

  • SP 250-XX: Calibration Services
  • SP 260-XX: Standard Reference Materials
  • SP 300-XX: Precision Measurement and Calibration
  • SP 400-XX: Semiconductor Measurement Technology
  • SP 480-XX: Law Enforcement Technology
  • SP 500-XX: Computer Systems Technology
  • SP 700-XX: Industrial Measurement Series
  • SP 800-XX: Computer Security Series
  • SP 823-XX: Integrated Services Digital Network Series