The data for 'Infrared spectra of methane-containing ice mixtures for JWST data analysis'

This dataset contains the supplementary data for the A&A paper 'Infrared spectra of methane-containing ice mixtures for JWST data analysis'. The laboratory transmittance infrared spectra in the 2.5--15.9 μm (4000--630 cm-1) region are presented for the CH_4 molecule in different enviroments at 6.7 K and 10 K. The ice analogues are grown utilizing ISEAge UHV cryogenic setup at the Research Laboratory for Astrochemistry, Ural Federal University. The FTIR spectra are recorded using the Thermo Scientific Nicolet iS50 FTIR spectrometer with the resolution of 1 cm-1. Please, refer to the main paper for the additional information. The dataset consists of 24 files, each containing a spectrum obtained after deposition at 6.7 K or 10 K with the metadata marked in a filename. The spectra are given as wavenumber in cm-1 (column 1, Wavenumber) and dimensionless absorbance (column 2, Absorbance). The dataset contains the following mixtures of interstellar ice analogues: Pure CH_4 CH_4 : NH_3 = 1 : 3 CH_4 : CH_3OH = 1 : 3 CH_4 : CO_2 = 1 : 5 CH_4 : CO_2 = 1 : 15 CH_4 : H_2O = 1 : 10 All the spectra are presented at 6.7 K and 10 K deposition temperatures. The spectra are presented in two variations: raw and baseline corrected. The corrections include a global baseline slope correction, and the 1300 cm-1 methane feature, which is relevant for fitting, is also corrected for the asymmetric thin-film interference artefact. It is necessary to cite both this dataset by Zenodo DOI and the Karteyeva et al. (2026) The Astronomy& Astrophysics publication when making use of these data, to fully describe the data processing.