| Datensatz noch nicht abgeschlossen | |
| Zugriffsnummer | 56564 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Traceable direct-absorption validation and line-strength determination of H2 quadrupole transitions at 2121.8 nm and 2222 nm |
| Autor(in); Institution |
Kumar, Midhun; 3.3, Physikalische Chemie, PTB-Braunschweig; Leibniz University Hannover, Hannover, GERMANY
Shilongo, Rosamunde; University of Namibia (UNAM), Windhoek, NAMIBIA
Roth, Bernhard; Leibniz University Hannover, Hannover, GERMANY
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| Quelle/Jahr | Measurement: 287 (2026) |
| Artikelnummer | 122450 |
| ISSN | 0263-2241 (print) ; 1873-412X (online) |
| DOI | |
| Freie Schlagworte | hydrogen ; tunable diode laser absorption spectroscopy ; Hartmann-Tran profile ; multipass cell ; integrated absorbancer ; repeatability ; traceability |
| Zusammenfassung | A traceable validation of the tunable diode laser absorption spectroscopy (TDLAS) measurement chain for hydrogen (H2), with line-strength determination, is reported for two near-infrared quadrupole transitions at 2121.8 nm and 2222 nm. Measurements used a dual-wavelength Herriott-type multipass cell with an effective optical path length of 3122.7 ± 2 cm. Spectra were evaluated by etalon-based spectral-axis reconstruction and constrained Hartmann–Tran-type (HTP-type) non-Voigt fitting; the area-normalized fit retrieves the integrated absorbance A, and Beer–Lambert pressure scaling of A yields the line strength, forming a single retrieval chain. Pure-H-sub.2 pressure-series experiments were repeated in independent measurement campaigns and evaluated without empirical recalibration. For the stronger 2121.8 nm transition, the repeated datasets gave a dataset-level reproducibility of 1.11% in A/p and a standard uncertainty of the mean of 0.39%. For the weaker 2222 nm transition, the evaluated datasets gave a dataset-level scatter of 1.35%. The resulting line strengths are S = (3.014 ± 0.034) × 10-26 cm molecule-1 at 2121.8 nm and S = (1.057 ± 0.014) × 10-26 cm molecule-1 at 2222 nm, deviating from HITRAN by -5.49% and -2.05%, respectively. Because the HITRAN intensities carry an assigned uncertainty of 0.1–1% (intensity uncertainty code 8), these deviations exceed the combined stated uncertainties, indicating a residual systematic contribution. The work establishes an SI-traceable direct-ab sorption chain for H2 quadrupole spectroscopy. |
| Themenbereich der Metrologie | Metrologie in der Chemie und Stoffeigenschaften |
| Förderinformationen (1) |
Titel der Förderung: European Partnership on Metrology project, European Union’s Horizon Europe Research and Innovation Programme Förderungsnummer: 24GRD11 MetroHyVe3 |
Zitierung
Kumar, M., Farzana, N., Shilongo, R., Fernandes, R., Shu, B., Roth, B., Agarwal, S., & Qu, Z. (2026). Traceable direct-absorption validation and line-strength determination of H₂ quadrupole transitions at 2121.8 nm and 2222 nm. Measurement, 287. https://doi.org/10.1016/j.measurement.2026.122450