Metrologia最新文献

{"title":"A robust time scale for space applications using the student’s t-distribution","authors":"Hamish McPhee, Jean-Yves Tourneret, David Valat, Jérôme Delporte, Yoan Grégoire and Philippe Paimblanc","doi":"10.1088/1681-7575/ad7606","DOIUrl":"https://doi.org/10.1088/1681-7575/ad7606","url":null,"abstract":"In this article, the principles of robust estimation are applied to the standard basic time scale equation to obtain a new method of assigning weights to clocks. Specifically, the Student’s t-distribution is introduced as a new statistical model for an ensemble of clocks that are experiencing phase jumps, frequency jumps or anomalies in their measurement links. The proposed robust time scale is designed to mitigate the effects of these anomalies without necessarily identifying them, but through applying a method of robust estimation for the parameters of a Student’s t-distribution. The proposed time scale algorithm using the Student’s t-distribution (ATST) is shown to achieve comparable robustness to phase jumps, frequency jumps, and anomalies in the measurements with respect to the AT1 oracle time scale. The AT1 oracle is a special realization of the AT1 time scale which corrects all anomalies by having prior knowledge of their occurrences. The similar performance of ATST and AT1 oracle suggests that the ATST algorithm is efficient for obtaining robustness with no prior knowledge or detection of the occurrences of anomalies.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142263943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A digital four-arm bridge for the comparison of resistance with capacitance","authors":"Yicheng Wang and Stephan Schlamminger","doi":"10.1088/1681-7575/ad7590","DOIUrl":"https://doi.org/10.1088/1681-7575/ad7590","url":null,"abstract":"We have built and demonstrated a digital four-arm bridge for the comparison of resistance with capacitance. The digital four-arm bridge mimics the classical quad bridge in the digital domain with three balances: the source balance, the detector balance, as well as the main balance. Due to correlation, the required precision of the source voltages is only of the order of the square root of the ultimate bridge precision. For the comparison of a 100 kΩ resistor with a 1 nF capacitor near 1592 Hz, the combined standard uncertainty is .","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Traceable characterisation of fibre-coupled single-photon detectors","authors":"Luke Arabskyj, Philip R Dolan, Adam L Parke, Ted S Santana, Simon R G Hall, Geiland Porrovecchio, Marek Smid, Marco Lucamarini, Christopher J Chunnilall","doi":"10.1088/1681-7575/ad70bc","DOIUrl":"https://doi.org/10.1088/1681-7575/ad70bc","url":null,"abstract":"The detection of single photons plays an essential role in advancing single-photon science and technologies. Yet, within the visible/near-infrared spectral region, accurate fibre-based optical power measurements at the few-photon level are not yet well-established. In this study, we report on a fibre-based setup, enabling traceable optical power measurements at the few-photon level in this spectral region. The setup was used to calibrate the detection efficiency (DE) of four single-photon avalanche diode (SPAD) detectors. The relative standard uncertainties on the mean DE values obtained from repeat fibre-to-detector couplings ranged from 0.67% to 0.81% (<italic toggle=\"yes\">k</italic> = 2). However, the relative standard deviation of DE values, which ranged from 1.38% to 3.20% (<italic toggle=\"yes\">k</italic> = 2), poses a challenge for the metrology of these devices and applications that require high accuracy and repeatability. We investigated the source of these variations by spatially mapping the response of a detector’s fibre connector port, using a focused free-space beam, allowing us to estimate the detector’s spatial non-uniformity. In addition, we realise a novel calibration approach for fibre-coupled SPADs in a free-space configuration, enabling a direct comparison between the fibre-based setup and the National Physical Laboratory’s established free-space facility using a single SPAD. Finally, we investigated alternative coupling methods, testing the repeatability of different fibre-to-fibre connectors in addition to direct fibre-to-detector couplings: SPADs from three manufacturers were tested, with both single-mode and multi-mode fibre.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An emf-temperature reference function for Pt–20%Rh versus Pt thermocouples in the temperature range of 0 °C to 1100 °C","authors":"F Edler, P Ederer, K Huang","doi":"10.1088/1681-7575/ad746b","DOIUrl":"https://doi.org/10.1088/1681-7575/ad746b","url":null,"abstract":"An electromotive force–temperature reference function for thermocouples made of platinum–20%rhodium versus platinum (Pt–20%Rh/Pt) was determined for the temperature range from 0 °C to 1100 °C. Three Pt–20%Rh/Pt thermocouples were constructed at the Physikalisch-Technische Bundesanstalt (PTB) and were compared with standard platinum resistance thermometers, an Au/Pt thermocouple and a Pt/Pd thermocouple, which were all calibrated at fixed points of the International Temperature Scale of 1990 (ITS-90). The comparison measurements were performed in stirred liquid baths in the range from 0 °C to 545 °C, in a sodium heat pipe from 560 °C to 980 °C, and in a five-zone furnace at temperatures between 1000 °C and 1100 °C. Furthermore, the Pt–20%Rh/Pt thermocouples were calibrated at fixed points of the ITS-90. The PTB reference function based on two of the three Pt–20%Rh/Pt thermocouples has an expanded measurement uncertainty of 0.25 K in the temperature range from 0 °C to 1100 °C.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase reconstruction by phase shift estimation with reliable parameter minimization","authors":"Yu Zhang, Bao Liu","doi":"10.1088/1681-7575/ad6b2f","DOIUrl":"https://doi.org/10.1088/1681-7575/ad6b2f","url":null,"abstract":"Achieving a balance between accuracy and speed in phase reconstruction is a challenging problem. In phase-shifting interferometry, increasing the speed by reducing the number of phase shifts while maintaining high accuracy is highly desirable. We propose an accurate and efficient two-step phase reconstruction method utilizing random phase shift. This method directly estimates the phase shift through reliable parameter minimization, allowing for easy and precise phase reconstruction. Simulations and experiments demonstrate the superior performance of our method across various scenarios, outperforming well-known two-step phase-shifting algorithms. We expect this paper to provide a general and powerful tool for phase reconstruction.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COOMET key comparison COOMET.PR-K1.a.2018 for spectral irradiance 250 nm to 2500 nmm, final report","authors":"B B Khlevnoy, M V Solodilov, S S Kolesnikova, D A Otryaskin, I V Korseko, S V Nikanenka, M V Huriev, F Sametoğlu","doi":"10.1088/0026-1394/61/1a/02001","DOIUrl":"https://doi.org/10.1088/0026-1394/61/1a/02001","url":null,"abstract":"<title>Main text</title>This report describes the Key Comparison COOMET.R-K1.a.2018 for spectral irradiance in the wavelength range of 250 nm to 2500 nm, conducted by the Regional Metrology Organization \"Euro-Asian Cooperation of National Metrological Institutions\" (COOMET). The comparison was, in fact, a combination of three bilateral comparisons with the same link/pilot laboratory - the All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI), the Russian Federation. The non-link laboratories were the Belarusian State Institute of Metrology (BelGIM), Belarus, the National Scientific Centre \"Institute of Metrology\" (NSC IM), Ukraine, and the National Metrology Institute of Türkiye (TÜBİTAK UME), Türkiye.The aim of the comparison was to link the BelGIM, NSC IM and TÜBİTAK UME measurement results to the CIPM key comparison CCPR-K1.a.2017, conducted by the Consultative Committee for Photometry and Radiometry (CCPR).Tungsten quartz halogen lamps of the FEL type (1000 W) were used as artefacts. Each participant used its own set of lamps. The sequence of measurements was <italic toggle=\"yes\">participant - pilot - participant</italic>. The pilot measurements of the described here COOMET comparison were performed in a short time (within three months) after completing the measurements of CCPR-K1.a.2017, where VNIIOFI also was a pilot, which provided a high quality link.NSC IM performed measurements in the full spectral range, from 250 nm to 2500 nm, while BelGIM and TÜBİTAK UME managed to cover the range from 250 nm to 1100 nm only.The analysis of the comparison was performed following the approach described in the Appendix A of the Guidelines for CCPR and RMO Bilateral Key Comparisons (CCPR-G5). Differences from KCRV of BelGIM and TÜBİTAK UME, for the most of the measured wavelengths, do not exceed 2% and are within the expanded uncertainties. For NSC IM the differences from KCRV are within or comparable with the uncertainties in the IR range, from 900 nm to 2500 nm, but become larger with decreasing wavelength in the visible and UV reaching 9% at 250 nm.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/coomet-pr-k1a-2018\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with CMS/ITRI, March 2024","authors":"Joële Viallon, Faraz Idrees, Philippe Moussay, Robert Wielgosz, Jim Norris, Peter Trask, Shih-Fang Chen, Yun Feng","doi":"10.1088/0026-1394/61/1a/08013","DOIUrl":"https://doi.org/10.1088/0026-1394/61/1a/08013","url":null,"abstract":"<title>Main text</title>As part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone standard of Chinese Taipei maintained by the Industrial Technology Research Institute/Center for Measurement Standards (CMS/ITRI) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/bipm-qm-k1_cms_2024\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with VSL, April 2024","authors":"Joële Viallon, Faraz Idrees, Philippe Moussay, Robert Wielgosz, Luuk Meijer, Adriaan van der Veen","doi":"10.1088/0026-1394/61/1a/08012","DOIUrl":"https://doi.org/10.1088/0026-1394/61/1a/08012","url":null,"abstract":"<title>Main text</title>As part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone standard of the Netherlands maintained by the Van Swinden Laboratorium (VSL) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/bipm-qm-k1_vsl_2024\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intercontinental frequency ratio measurement of 171 Yb and 88 Sr optical lattice clocks","authors":"Piotr Morzyński, Sławomir Bilicki, Marcin Bober, Domagoj Kovačić, Roman Ciuryło, Michał Zawada, Jerzy Nawrocki, Piotr Dunst, Takumi Kobayashi, Kazumoto Hosaka, Daisuke Akamatsu","doi":"10.1088/1681-7575/ad6a1e","DOIUrl":"https://doi.org/10.1088/1681-7575/ad6a1e","url":null,"abstract":"We report a remote, intercontinental frequency comparison between ¹⁷¹Yb (NMIJ) and ⁸⁸Sr (UMK) optical lattice clocks. The frequencies were compared via the Global Positioning System Precise Point Positioning technique over the period from 10 March 2020, 00:00 UTC until 15 March 2020, 00:00 UTC. The comparison of the optical clocks yields results with a relative frequency uncertainty of <inline-formula>\u0000<tex-math><?CDATA $6.3times 10^{-15}$?></tex-math>\u0000<mml:math overflow=\"scroll\"><mml:mrow><mml:mn>6.3</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mn>10</mml:mn><mml:mrow><mml:mo>−</mml:mo><mml:mn>15</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>\u0000<inline-graphic xlink:href=\"metad6a1eieqn3.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Update of the BIPM comparison BIPM.RI(II)-K1.Co-57 of activity measurements of the radionuclide 57Co to include the 2023 result of the BEV (Austria)","authors":"Romain Coulon, Carine Michotte, Sammy Courte, Manuel Nonis, Vincent Gressier, Robert Brettner-Messler, Patrick Lobner, Isabelle Mercedes Taschwer","doi":"10.1088/0026-1394/61/1a/06011","DOIUrl":"https://doi.org/10.1088/0026-1394/61/1a/06011","url":null,"abstract":"<title>Main text</title>Since 1976, 20 laboratories have submitted 59 samples of ⁵⁷Co to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Co-57. Recently, the BEV (Austria) participated in the comparison. The degrees of equivalence between each equivalent activity measured in the SIR or linked to the SIR from the CCRI(II)-S6.Co-57 comparison have been calculated and the results are given in the form of a table. A graphical representation is also given.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/bipm-ri-ii-k1-co-57_bev_2023\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}