New beyond-Voigt line-shape pro le recommended for the HITRAN database

Published

March 27, 2025

Author(s)

Piotr Wcislo, N. Stolarczyk, M. Słowiński, H. Jóźwiak, Daniel Lisak, R. Ciuryło, A. Cygan, F. Schreier, C.D. Boone, A. Castrillo, L. Gianfrani, Y. Tan, S-M. Hu, Erin Adkins, Joseph Hodges, H. Tran, H.N. Ngo, J.M- Hartmann, A. Campargue, S. Beguier, R.J. Hargreaves, L.S. Rothman, I.E. Gordon

Abstract

Parameters associated with the collisional perturbation of spectral lines are essential for modeling the absorption of electromagnetic radiation in planetary atmospheres. The HITRAN molecular spectroscopic database provides these parameters, although originally, they were associated only with the Voigt pro le parametrization. However, in HITRAN2016 and HITRAN2020 editions of the database Voigt, speed-dependent Voigt and Hartmann-Tran (HT) pro les have been incorporated, thanks to the new relational structure of the database. The HT pro le was introduced in HITRAN in 2016 as a recommended pro le for the most accurate spectral interpretations and modeling. This pro le was parameterized with a four-temperature-range temperature dependence. Since then, however, the HT pro le has revealed some features that are problematic from a practical perspective. The two most problematic features are: the singular behavior of the temperature dependencies of the velocity-changing parameters when the shift parameter crosses zero and the diculty in evaluating the velocity-changing parameters for mixtures. In this article, we sum up the e orts aimed at eliminating the above-mentioned problems that led us to recommend using the quadratic speeddependent hard-collision (qSDHC) pro le with double-power-law (DPL) temperature dependencies. We refer to this pro le as a modi ed Hartmann-Tran (mHT) pro le. The computational cost of evaluating the mHT pro le is the same as for the HT pro le. We give a detailed description of the mHT pro le (also including line mixing) and discuss the representation of its parameters, together with their DPL temperature parametrization, adopted in the HITRAN database. We discuss the ecient algorithm for evaluating the mHT pro le and provide corresponding computer codes for it in several programming languages: FORTRAN, Python, Matlab, Mathematica, and LabView. We also discuss the corresponding update of the HITRAN Application Programming Interface (HAPI).

Citation

Journal of Quantitative Spectroscopy and Radiative Transfer

Pub Type

Journals

Keywords

lineshape

Citation

Wcislo, P. , Stolarczyk, N. , Słowiński, M. , Jóźwiak, H. , Lisak, D. , Ciuryło, R. , Cygan, A. , Schreier, F. , Boone, C. , Castrillo, A. , Gianfrani, L. , Tan, Y. , Hu, S. , Adkins, E. , Hodges, J. , Tran, H. , Ngo, H. , Hartmann, J. , Campargue, A. , Beguier, S. , Hargreaves, R. , Rothman, L. and Gordon, I. (2025), New beyond-Voigt line-shape pro le recommended for the HITRAN database, Journal of Quantitative Spectroscopy and Radiative Transfer (Accessed June 29, 2025)