988 lines
81 KiB
Text
988 lines
81 KiB
Text
<!DOCTYPE html>
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<html lang="en" dir="ltr" prefix="content: http://purl.org/rss/1.0/modules/content/ dc: http://purl.org/dc/terms/ foaf: http://xmlns.com/foaf/0.1/ og: http://ogp.me/ns# rdfs: http://www.w3.org/2000/01/rdf-schema# schema: http://schema.org/ sioc: http://rdfs.org/sioc/ns# sioct: http://rdfs.org/sioc/types# skos: http://www.w3.org/2004/02/skos/core# xsd: http://www.w3.org/2001/XMLSchema# ">
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<h1 class="nist-page__title">New measurement of the Boltzmann constant k by acoustic thermometry of helium-4 gas</h1>
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<div class="nist-field__label">Published</div>
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<div class="nist-field__item"><time datetime="2017-09-11T12:00:00Z">September 11, 2017</time>
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<h3 class="nist-field__label">Author(s)</h3>
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<div class="nist-field__item">Laurent Pitre, Fernando Sparasci, <span class="nist-author">Michael R. Moldover</span>, Cecile Guianvarch, Catherine Martin, Martin Himbert, Mark Plimmer, James B. Mehl, Giuliano Albo, Bo Gao, Lara Risegari</div>
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<h3>Abstract</h3>
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The SI unit of temperature will soon be redefined in terms of a fixed value of the Boltzmann constant k derived from an ensemble of measurements worldwide. We report on a new determination of k using acoustic thermometry of helium-4 gas in a 3-litre quasi-sphere. The method is similar to that used in our own experiments on helium and argon with a 0.5-litre resonator. We find for the universal gas constant R = 8.3144597 (49) J·mol-1·K-1. Using the current best available value of the Avogadro constant, we obtain k = 1.38064849 (81) ×10-23 J·K-1 and ur(k) = 0.59x10-6, where the uncertainty is one standard uncertainty corresponding to a 68 % confidence level. This value is in good agreement with those of our earlier measurements and with that of the 2014 CODATA adjustment of the fundamental constants, within the standard uncertainties.
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<div class="nist-field__item">Metrologia</div>
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<div class="nist-field__label">Volume</div>
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<div class="nist-field__item">54</div>
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<div class="nist-field__item">6</div>
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<div class="nist-field__item"><a href="https://doi.org/10.1088/1681-7575/aa7bf5" target="_blank">https://doi.org/10.1088/1681-7575/aa7bf5</a></div>
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<h3 class="nist-field__label">Keywords</h3>
|
||
<div class="nist-field__item">Boltzmann constant, acoustic thermometry, temperature scale, resonator, Gas constant, fundamental constants</div>
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<article class="bibcite-reference">
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<div class="bibcite-citation">
|
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Pitre, L.
|
||
, Sparasci, F.
|
||
, Moldover, M.
|
||
, Guianvarch, C.
|
||
, Martin, C.
|
||
, Himbert, M.
|
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, Plimmer, M.
|
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, Mehl, J.
|
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, Albo, G.
|
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, Gao, B.
|
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and Risegari, L.
|
||
|
||
(2017),
|
||
New measurement of the Boltzmann constant k by acoustic thermometry of helium-4 gas, Metrologia, [online], https://doi.org/10.1088/1681-7575/aa7bf5, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923465
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(Accessed March 4, 2025)
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If you have any questions about this publication or are having problems accessing it, please contact <a href="mailto:reflib@nist.gov" class="usa-link">reflib@nist.gov</a>.
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<div class="text-italic font-sans-2xs">
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Created September 10, 2017, Updated October 12, 2021
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