OOIR: Observatory of International Research

Papers

(The median citation count of Metrologia is 1. The table below lists those papers that are above that threshold based on CrossRef citation counts [max. 250 papers]. The publications cover those that have been published in the past four years, i.e., from 2020-04-01 to 2024-04-01.)

Article	Citations
Absolute frequency measurement of the ¹S₀–³P₀ transition of ¹⁷¹Yb with a link to international atomic time	47
First accuracy evaluation of the NRC-FCs2 primary frequency standard	29
Optical frequency ratio of a ¹⁷¹Yb⁺ single-ion clock and a ⁸⁷Sr lattice clock	26
Demonstration of the nearly continuous operation of an¹⁷¹Yb optical lattice clock for half a year	25
Traceability of digital 3-axis MEMS accelerometer: simultaneous determination of main and transverse sensitivities in the frequency domain	25
Characterization of a newly developed diaphragmless shock tube for the primary dynamic calibration of pressure meters	24
Absolute frequency measurement of the ¹⁷¹Yb optical lattice clock at KRISS using TAI for over a year	23
A strontium optical lattice clock with 1 × 10⁻¹⁷ uncertainty and measurement of its absolute frequency	22
Direct comparisons of European primary and secondary frequency standards via satellite techniques	20
Beginning of a new phase of the dissemination of the kilogram	20
On using converging shock waves for pressure amplification in shock tubes	20
The BIPM Kibble balance for realizing the kilogram definition	18
Sensing characteristics of photonic crystal fiber Sagnac interferometer based on novel birefringence and Vernier effect	18
A ⁸⁷Sr optical lattice clock with 2.9 × 10⁻¹⁷ uncertainty and its absolute frequency measurement	18
Absolute frequency measurement of an Yb optical clock at the 10⁻¹⁶ level using International Atomic Time	18
Measurement of thermodynamic temperature between 5 K and 24.5 K with single-pressure refractive-index gas thermometry	18
Absolute frequency of ⁸⁷Sr at 1.8 × 10⁻¹⁶ uncertainty by reference to remote primary frequency standards	17
Experimental quantum polarimetry using heralded single photons	17
Review of field characterization techniques for high intensity therapeutic ultrasound	17
The international reference system for pure β-particle emitting radionuclides: an investigation of the reproducibility of the results	16
Dual Josephson impedance bridge: towards a universal bridge for impedance metrology	16
Standard platinum resistance thermometer interpolations in a revised temperature scale	16
Thermodynamic-temperature data from 30 K to 200 K	15
Analysis on the time transfer performance of BDS-3 signals	15
The new mise en pratique for the metre—a review of approaches for the practical realization of traceable length metrology from 10⁻¹¹ m to 10¹³ m	15

Reduction of calibration uncertainty due to mounting of three-axis accelerometers using the intrinsic properties model	15
High-performance coherent population trapping atomic clock with direct-modulation distributed Bragg reflector laser	14
Refractive index gas thermometry between 13.8 K and 161.4 K	13
The performance of the KIBB-g1 tabletop Kibble balance at NIST	13
The international reference system for pure beta-particle emitting radionuclides: an evaluation of the measurement uncertainties	13
First uncertainty evaluation of the cesium fountain primary frequency standard NMIJ-F2	12
Calibrating spectrometers for measurements of the spectral irradiance caused by solar radiation	12
A novel method for simultaneous measurement of thickness, refractive index, bow, and warp of a large silicon wafer using a spectral-domain interferometer	12
Algorithms for using silicon steps for scanning probe microscope evaluation	11
Advances in traceable calibration of cylinder pressure transducers	11
Realization of the kilogram using the KRISS Kibble balance	11
Precision measurement of single-electron current with quantized Hall array resistance and Josephson voltage	11
Thermodynamic effects in a gas modulated Invar-based dual Fabry–Pérot cavity refractometer	11
Absolute energies and emission line shapes of the L x-ray transitions of lanthanide metals	11
Empirical decomposition and error propagation of medium-term instabilities in half-life determinations	10
Generating a real-time time scale making full use of the available frequency standards	10
Guidance on Bayesian uncertainty evaluation for a class of GUM measurement models	10
Establishing waveguide lines as primary standards for scattering parameter measurements at submillimetre wavelengths	10
Ytterbium optical lattice clock with instability of order 10⁻¹⁸	10
Primary calibration system for digital accelerometers	10
Transient heating in fixed length optical cavities for use as temperature and pressure standards	9
On the influence of inlet perturbations on slug dynamics in horizontal multiphase flow—a computational study	9
A simple method for Bayesian uncertainty evaluation in linear models	9
The upgrade of NIM-2 joule balance since 2017	9
The self-attraction effect in an atom gravity gradiometer	9
Continuous IPPP links for UTC	8
Highly-accurate second-virial-coefficient values for helium from 3.7 K to 273 K determined by dielectric-constant gas thermometry	8
Refining the cold atom pressure standard	8
Improved frequency ratio measurement with ⁸⁷Sr and ¹⁷¹Yb optical lattice clocks at NMIJ	8
Updated measurement method and uncertainty budget for direct emissivity measurements at the University of the Basque Country	8
Achieving traceability to UTC through GNSS measurements	8
A three-cornered hat analysis of instabilities in two-way and GPS carrier phase time transfer systems	8
Prenormative verification and validation of a protocol for measuring magnetite–maghemite ratios in magnetic nanoparticles	8
Second solar ultraviolet radiometer comparison campaign UVC-II	8
Preliminary study of generating a local time scale with NIM ⁸⁷Sr optical lattice clock	7
The comparability of the determination of the molar mass of silicon highly enriched in ²⁸Si: results of the CCQM-P160 interlaboratory comparison and additional external measurements	7
Establishment of 2π total spectral radiant flux scale with a broadband LED-based transfer standard source	7
Perchlorate ion standard solution: multipath titrimetric approach using three different stoichiometric reactions—towards the establishment of SI traceable chemical standards	7
Realization and evaluation of the triple point of sulfur hexafluoride	7
Survey of subrange inconsistency of long-stem standard platinum resistance thermometers	7
Precise measurements of super-high reflectance with cavity ring-down technique	7
Measurement of the ²⁷Al⁺ and ⁸⁷Sr absolute optical frequencies	7
Two-point diameter calibration of a sphere using a micro-coordinate measuring machine at NMIJ	7
CCQM-K68.2019, nitrous oxide (N₂O) in air, ambient level, final report	7
Radiometric characterization of a triggered narrow-bandwidth single-photon source and its use for the calibration of silicon single-photon avalanche detectors	7
Consistency in Monte Carlo Uncertainty Analyses	7
Towards a consensus on a continuous coordinated universal time	7
Precise sinusoidal signal extraction from noisy waveform in vibration calibration	7
Angles in the SI: treating the radian as an independent, unhidden unit does not require the redefinition of the term ‘frequency’ or the unit hertz	7
Precise density measurement and its uncertainty evaluation for refractory liquid metals over 3000 K using electrostatic levitation	7

Uncertainty evaluations from small datasets	7
A new calibration setup for lock-in amplifiers in the low frequency range and its validation in a bilateral comparison	6
An optimized sampling system for highly reproducible isotope ratio measurements (δ ¹³C and δ ¹⁸O) of pure CO₂ gas by infrared spectroscopy	6
Metrological approach of γ-emitting radionuclides identification at low statistics: application of sparse spectral unmixing to scintillation detectors	6
A critical review of the common thermocouple reference functions	6
A laser pistonphone designed for absolute calibration of infrasound sensors from 10 mHz up to 20 Hz	6
SI-traceable solar irradiance measurements for aerosol optical depth retrieval	6
On the uncertainties in the realization of the kelvin based on thermodynamic temperatures of high-temperature fixed-point cells	6
A fully digital bridge towards the realization of the farad from the quantum Hall effect	6
Measurement configurations for differential sampling of AC waveforms based on a programmable Josephson voltage standard: effects of sampler bandwidth on the measurements	6
Linearity of a silicon carbide photodiode in the deep-UV spectral region: implications on Doppler broadening thermometry	6
A first step towards the introduction of redundant time links for the generation of UTC: the calculation of the uncertainties of [UTC-UTC(k)]	6
Role of measurement uncertainty in the comparison of average areal rainfall methods	6
Thickness and refractive index measurements of a thin-film using an artificial neural network algorithm	6
An AC quantum voltmeter for frequencies up to 100 kHz using sub-sampling	6
Final report on the CIPM key comparison CCAUV.V-K5	6
Revisiting the limits of photon momentum based optical power measurement method, employing the case of multi-reflected laser beam	6
Determination of the responsivity of a predictable quantum efficient detector over a wide spectral range based on a 3D model of charge carrier recombination losses	6
A metrological approach to quantities that are counted and the unit one	6
Acoustic measurement of the triple point of neon T _Ne and thermodynamic calibration of a transfer standard for accurate cryogenic thermometry	6
Improved absolute frequency measurement of the strontium ion clock using a GPS link to the SI second	5
Axial force radiometer for primary standard laser power measurements using photon momentum	5
Primary standard for the number concentration of liquid-borne particles: extension of the diameter range from the micrometer to the sub-micrometer level and reduction of the measurement uncertainty	5
A comparison of traceable spatial angle autocollimator calibrations performed by PTB and VTT MIKES	5
Correction factors for primary beta dosimetry	5
High amplification laser-pressure optic enables ultra-low uncertainty measurements of optical laser power at kilowatt levels	5
Accounting for polarization–related effects in the measurement of the bidirectional reflectance distribution function	5
Evaluation of effective area of air piston gauge with limitations in piston–cylinder dimension measurements	5
Towards traceable dynamic pressure calibration using a shock tube with an optical probe for accurate phase determination	5
Traceability for nuclear medicine: the status of primary radioactivity standards	5
Absolute frequency measurement of the ⁸⁷Sr optical lattice clock at NTSC using international atomic time	5
Bayesian inference for heterogeneity in meta-analysis	5
Thickness measurements and uncertainty evaluation of a multilayer thin-film sample using auxiliary single-layer samples	5
Corrigendum: Realization of the triple point of carbon dioxide evaluated by the ITS–90 (2020 Metrologia 57 015004)	5
Finite element analysis of blackbody radiation environment for an ytterbium lattice clock operated at room temperature	5
ITS-90 reproducibility, xenon fixed point substitution and new interpolating equations between 13.8033 K and 273.16 K	5
Coherent fiber links operated for years: effect of missing data	5
Final report of the new BIPM comparison BIPM.RI(II)-K1.Ra-223 of activity measurements of the radionuclide ²²³Ra including the 2014 result of the NPL (United Kingdom), the 2014 result of th	5
On the long-term stability of the triple-point-of-water cells	5
Realization of a free-running timescale based on a CsF1 cesium fountain clock and multiple active hydrogen masers	5
Final report on the CCM key comparison of kilogram realizations CCM.M-K8.2021	5
Robustness tests for an optical time scale	5
Method to traceably determine the refractive index by measuring the angle of minimum deviation	5
Direct comparison of ITS-90 and PLTS-2000 from 0.65 K to 1 K at LNE-CNAM	4
Mass fraction assignment of Bisphenol-A high purity material	4
Detection and identification of faults in clock ensembles with the generalized likelihood ratio test	4
Terahertz frequency counter based on a semiconductor-superlattice harmonic mixer with four-octave measurable bandwidth and 16-digit precision	4
Calibration of GNSS stations for UTC	4
A method for calibrating forward scatter meters indoors	4
Defining relative humidity in terms of water activity: III. Relations to dew-point and frost-point temperatures	4
International comparison CCQM-K117 ammonia	4
Artifacts and errors in cross-spectrum phase noise measurements	4
Precise measurement of the thickness of silicon wafers by double-sided interferometer and bilateral comparison	4
Measurements of absolute, SI-traceable lunar irradiance with the airborne lunar spectral irradiance (air-LUSI) instrument	4
Evaluation of different general V(λ) mismatch indices of photometers for LED-based light sources in general lighting applications	4
Thickness measurement of nm HfO₂ films	4
Remote time and frequency calibration with holdover traceability from a new treatment of non-white noise in rubidium clocks	4
A bilateral comparison of NIST and PTB laser power standards for scale realization confidence by gravitational wave observatories	4
PAWG Pilot Study on Quantification of SARS-CoV-2 Monoclonal Antibody - Part 1	4
Precision measurement of an electron pump at 2 GHz; the frontier of small DC current metrology	4
The value of stable, comparable and standardised measurement: enabling confidence in decision making for societal challenges	4
Interlaboratory consensus building	4
Experimental validation of theoretically predicted cut-off of L₁–L₃M_4,5 transitions at Z = 50 through measurements of fluorescence and Coster–Kronig yi	4
Report of the CCQM-K152. Assay of potassium iodate	4
First realisation of the kilogram with the METAS Kibble balance	4
CCQM-K143 comparison of copper calibration solutions prepared by NMIs/DIs	4
The irony of the magnet system for Kibble balances—a review	4
What is a mole?	4
Final report for supplementary comparison APMP.QM-S9.2017: 100 μmol/mol of carbon monoxide in nitrogen	4
Angles in the SI: a detailed proposal for solving the problem	4
Final report on CCQM-K167: carbon isotope delta measurements of vanillin	4
The CCRI(II)-K2.Fe-55.2019 key comparison of activity concentration measurements of a ⁵⁵Fe solution	4
Proposal for the dimensionally consistent treatment of angle and solid angle by the International System of Units (SI)	4
Gonioreflectometer for measuring 3D spectral BRDF of horizontally aligned samples with traceability to SI	4
Primary thermometry at 4 K, 14 K, and 25 K applying dielectric-constant gas thermometry	4
Evaluation of the transportable atom gravimeter HUST-QG	4
Evaluation of blackbody radiation shift with 2 × 10⁻¹⁸ uncertainty at room temperature for a transportable ⁴⁰Ca⁺ optical clock	4
On the dimension of angles and their units	4
Emissivities of vacuum compatible materials: towards minimising blackbody radiation shift uncertainty in optical atomic clocks at room temperatures	3
International comparison of activity measurements of radon 222 - EURAMET Project n°1475 - EURAMET.RI(II)-S8.Rn-222	3

Qualification and frequency accuracy of the space-based primary frequency standard PHARAO	3
Economic optimization of acceptance interval in conformity assessment: 2. Process with unknown systematic effect	3
Characterization of predictable quantum efficient detector in terms of optical non-linearity in the visible to near-infrared range	3
Some predictions of a validated physical model of Pt–Rh thermocouple drift above 1200 °C	3
Comment on ‘Angles in the SI: a detailed proposal for solving the problem’	3
Improved Raman pulse sequence for rotation measurements with atom interferometers	3
Increased detector response in optical overfilled measurements due to gas lens formation by nitrogen flow through the entrance aperture	3
Speedy in-situ magnetic field compensation algorithm for multiple-channel single-beam SERF atomic magnetometers	3
Economic optimization of acceptance interval in conformity assessment: 1. Process with no systematic effect	3
Correction factors for two new reference beta radiation fields	3
A comparison of different calibration strategies for the trace analysis of soil samples by inductively coupled plasma mass spectrometry (ICP-MS)	3
Verification of an in situ calibrated optomechanical accelerometer for use as a strong ground motion seismic reference	3
Measurement of miscut angles in the determination of Si lattice parameters	3
Rejection sampling for Bayesian uncertainty evaluation using the Monte Carlo techniques of GUM-S1	3
Gas flow standards and their uncertainty	3
Activity measurements of the radionuclides ^99mTc, ¹⁸F and ⁶⁴Cu for the POLATOM, Poland, in the ongoing comparisons BIPM.RI(II)-K4 series and KCRV update in the corres	3
Uncertainty budget for PTB’s gonioreflectometers and ways to improve it in the short VIS spectral range	3
Errors-in-variables calibration with dark uncertainty	3
Spaceborne radiance temperature standard blackbody for Chinese high-precision infrared spectrometer	3
Uncertainty analysis of stack gas flow measurements with an S-type Pitot tube for estimating greenhouse gas emissions using a continuous emission monitoring system	3
The non-uniqueness of ITS-90 above the silver point and its impact on values of T − T ₉₀	3
Roadmap towards the redefinition of the second	3
Advances in metrology for energy-containing gases and emerging demands	3
International comparison CCQM-K74.2018: Nitrogen dioxide, 10 μmol mol-1	3
Mid-infrared spectral responsivity scale based on an absolute cryogenic radiometer and a tunable quantum cascade laser	3
A constant pressure flowmeter for extreme-high vacuum	3
Development of a primary measurement standard for trace moisture in Ar	3
A further short history of the SI prefixes	3
Key Comparison Study - Organic Solvent Calibration Solution - Gravimetric preparation and value assignment of aflatoxin B1 (AfB1) in acetonitrile (ACN)	3
Effects of fast x-ray cone-beam tomographic measurement on dimensional metrology	3
A generalizable formalism for computing uncertainties in UTC	3
International comparison CCQM-K118 natural gas	3
Long-term drift analysis of Zener voltage standards and proposal of an initial calibration interval using calibration records accumulated for 15 years	3
Final report of the new BIPM comparison BIPM.RI(II)-K1.Ac-225 of activity measurements of the radionuclide ²²⁵Ac to include the 2019 result of the PTB (Germany)	3
Final report for supplementary comparison APMP.QM-S15: carbon dioxide in nitrogen at 1000 μmol/mol	3
The least informative distribution and correlation coefficient of measurement results	3
Quantification of ferritin-bound iron in murine samples for Alzheimer’s disease studies using species-specific isotope dilution mass spectrometry	2
Update of the BIPM comparison BIPM.RI(II)-K1.Ac-225 of activity measurements of the radionuclide ²²⁵Ac to include the 2021 result of the POLATOM (Poland)	2
A dynamic gravimetric standard for liquid flow measurements	2
Key comparison BIPM.RI(I)-K3 of the air-kerma standards of the KRISS, Republic of Korea, and the BIPM in medium-energy x-rays	2
A novel high accuracy micrometer for the measurement of diameter	2
Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with DMDM, September 2022	2
ITS-90 SPRT calibration from the Ar TP to the Zn FP	2
Quantification of titanium dioxide (TiO₂) anatase and rutile polymorphs in binary mixtures by Raman spectroscopy: an interlaboratory comparison	2
Accurate ground-to-ground laser time transfer by diffuse reflections from tumbling space debris objects	2
Automatic alignment technique for the suspended coil in the joule balance	2
Final report of the new BIPM comparison BIPM.RI(II)-K1.Tb-161 of activity measurements of the radionuclide ¹⁶¹Tb including the 2019 result of the IRA (Switzerland)	2
Temperature dependence correction method of LED filament lamp for total luminous flux calibration based on voltage measurement	2
Calibration process and uncertainty estimation for 3D pitot tubes to enhance greenhouse gas emission measurements in smokestacks	2
Update of the BIPM comparison BIPM.RI(II)-K1.Gd-153 of activity measurements of the radionuclide ¹⁵³Gd to include the 2020 result of the NIST (United States)	2
A high precision VIS/NIR dynamic goniometer-spectrometer	2
Pilot study on peptide purity - glycated hexapeptide of HbA1c	2
Effects of rotation errors on goniometric measurements	2
Key Comparison CCQM-K73.2018 Amount Content of H⁺ in Hydrochloric Acid (0.1 mol·kg⁻¹)	2
Final report of CCQM-P204, comparison on CO₂ isotope ratios in pure CO₂	2
NRC measurement set-up and preparatory work for CCT-K7.2021 key comparison of triple-point-of-water cells	2
PTB–INRIM comparison of novel digital impedance bridges with graphene impedance quantum standards	2
Determination of sensitivity coefficients and their uncertainties in Rockwell hardness measurement: a Monte Carlo method for multiple linear regression	2
Evaluation of long-term robustness of the International System of Reference (SIR) used in radionuclide metrology based on the meta-analysis of its machine-readable database	2
Quantification of single-strand DNA by sequence-specific counting in capillary flow cytometry	2
Key comparison BIPM.RI(I)-K2 of the air-kerma standards of the KRISS, Republic of Korea, and the BIPM in low-energy x-rays	2
Efficient experimental sampling through low-rank matrix recovery	2
Residual resistance ratio as indicator for the influence of impurities on fixed-point temperatures	2
Type A uncertainty analysis validation of type B analysis for three-axis accelerometer calibrations	2
Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the NIM, China and the BIPM in ⁶⁰Co gamma radiation	2
The unusual status of the hectare in the SI	2
Newtonian gravitational constant measurement. All atomic variables become extreme when using a source mass consisting of three or more parts	2
The kilogram: inertial or gravitational mass?	2
A digital framework for realising the SI—a proposal for the metre	2
Comparison of four-terminal-pair 1 pF, 10 pF, 100 pF and 1000 pF capacitance standards at frequencies of 10 kHz, 100 kHz, 1 MHz and 10 MHz (APMP.EM-S15)	2
Melting and freezing behavior of pure Ni cells in alumina crucibles with different internal structures	2
PAWG pilot study on quantification of SARS-CoV-2 monoclonal antibody - Part 2	2
Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the GUM, Poland and the BIPM in ⁶⁰Co gamma radiation	2
Traceable spectral interferometry for length measurement	2
Comparison in dynamic primary calibration of digital-output accelerometer between CEM and PTB	2
Calculation of magnetic forces and torques on the Kibble coil	2
Update of the BIPM comparison BIPM.RI(II)-K1.Co-60 of activity measurements of the radionuclide ⁶⁰Co to include the 2020 result of the PTB (Germany), the 2020 result of the NIST (United Sta	2
Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the GUM, Poland and the BIPM in ⁶⁰Co gamma radiation	2
UME Kibble balance operating in air	2
Novel developments of refractive power measurement techniques in the automotive world	2
Phase shifting angle interferometer	2
Primary standard for traceability in low liquid hydrocarbon fuel flow rates	2
Understanding immersion in zinc fixed-point cells using factorial design of experiments	2
Ode to Bayesian methods in metrology	2
Update of the BIPM comparison BIPM.RI(II)-K1.Sr-85 of activity measurements of the radionuclide ⁸⁵Sr to include the 2018 result of the PTB (Germany)	2
Long-term spectral responsivity stability of predictable quantum efficient detectors	2
Assay of sodium carbonate	2
COOMET supplementary comparison on wavelength for fiber optics	2
International comparison CCQM-K10.2018: BTEX in nitrogen at 5 nmol mol⁻¹	2
Primary calibration for airborne infrasound utilizing the vertical gradient of the ambient pressure	2
New metrological capabilities for measurements of dynamic liquid flows	2
Ambient humidity, the overlooked influencer of radioactivity measurements	2
Evaluation of the blackbody radiation shift of an Yb optical lattice clock at KRISS	2
Uncertainty in the mutual calibration method for the traceable thickness measurement of ultra-thin oxide films	2
Reply to Comment on ‘Angles in the SI: a detailed proposal for solving the problem’	2