Journal of Quantitative Spectroscopy & Radiative Transfer最新文献

{"title":"Quality control for infrared radiance of geostationary meteorological satellite using imaginary signal of Fourier transform spectroscopy","authors":"Yoshifumi Ota","doi":"10.1016/j.jqsrt.2025.109733","DOIUrl":"10.1016/j.jqsrt.2025.109733","url":null,"abstract":"<div><div>In this study, we explored the spectral characteristics of radiance data collected by the Geostationary Interferometric Infrared Sounder (GIIRS) aboard the Feng-Yun-4B (FY-4B) geostationary meteorological satellite. We compared GIIRS brightness temperature observations with the first guess from the regional numerical weather forecast model of the Japan Meteorological Agency, and analyzed the bias errors in brightness temperature under clear-sky conditions. In the longwave band, we observed checkerboard patterns of bias error distributions in the CO₂ channel. Focusing on the imaginary signals from the radiance data obtained through interferometry with a Fourier transform spectrometer, we believe that the observed bias errors are primarily attributed to electrical factors rather than GIIRS interferometry itself, and most of these errors can be corrected by estimating them in advance. Conversely, in the midwave band, we observed concave bias error distributions in the GIIRS instrument’s dwell, indicating that these may be related to GIIRS interferometry. Additionally, we examined the characteristics of the imaginary signal under cloudy conditions by comparing it with the cloud physical property products from Himawari-9. It was observed that large imaginary signals tended to appear in GIIRS data for scenes with high clouds and low brightness temperatures. This indicates that the imaginary signal could serve as auxiliary information for assessing whether observations are influenced by clouds, particularly high clouds including optically thin cirrus clouds. For the quantitative use of GIIRS data, it is important to consider these bias errors and perform quality control using the imaginary signal.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109733"},"PeriodicalIF":1.9,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145423986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-resolution ro-vibrational analysis of HCFC-22: Deciphering ν4 and 2ν6 bands of 12CH35ClF2 and ν4 band of 13CH35ClF2 species","authors":"Egor O. Dobrolyubov ,&nbsp;Ilya M. Efremov ,&nbsp;Sergey V. Krasnoshchekov ,&nbsp;Igor V. Polyakov ,&nbsp;Vladimir B. Laptev ,&nbsp;Sergey A. Klimin ,&nbsp;Dmitry V. Millionshchikov ,&nbsp;Olga V. Naumenko","doi":"10.1016/j.jqsrt.2025.109721","DOIUrl":"10.1016/j.jqsrt.2025.109721","url":null,"abstract":"&lt;div&gt;&lt;div&gt;A ro-vibrational analysis of a high-resolution IR spectrum of an isotopic mixture of the atmospheric pollutant chlorodifluoromethane (HCFC-22), enriched in &lt;sup&gt;13&lt;/sup&gt;C to 29.8 ± 0.14%, was performed in the range of 779–849 cm&lt;sup&gt;−1&lt;/sup&gt;, and the identification of spectral features was limited to most abundant species &lt;sup&gt;12&lt;/sup&gt;CH&lt;sup&gt;35&lt;/sup&gt;ClF2 and &lt;sup&gt;13&lt;/sup&gt;CH&lt;sup&gt;35&lt;/sup&gt;ClF&lt;sub&gt;2&lt;/sub&gt;. The spectrum was recorded on a Bruker IFS-125HR FT spectrometer at room temperature with a resolution of &lt;span&gt;&lt;math&gt;&lt;mo&gt;≈&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt;0.001 cm&lt;sup&gt;−1&lt;/sup&gt;. The inverse spectroscopic problem for the main isotopologue &lt;sup&gt;12&lt;/sup&gt;CH&lt;sup&gt;35&lt;/sup&gt;ClF&lt;sub&gt;2&lt;/sub&gt; was solved with Watson-type &lt;span&gt;&lt;math&gt;&lt;mi&gt;A&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;-reduced effective Hamiltonian (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;eff&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;) with accounting of the &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; Fermi resonance and the &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; Coriolis resonance. The identified 3003 transitions of &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and 1265 transitions of &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; produced 1598 empirical upper energy levels of the &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;J&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;81&lt;/mn&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;13&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) and 840 levels of the &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; band (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;J&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;71&lt;/mn&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;11&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) with RMSD = 2.92&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;×&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; cm&lt;sup&gt;−1&lt;/sup&gt;. For the &lt;sup&gt;13&lt;/sup&gt;CH&lt;sup&gt;35&lt;/sup&gt;ClF&lt;sub&gt;2&lt;/sub&gt; isotopologue, 670 transitions and corresponding empirical 350 energy levels of &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; band (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;J&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;34&lt;/mn&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) were identified for the first time. The effective model consisted of a &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ν&lt;/mi&gt;","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109721"},"PeriodicalIF":1.9,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145412040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of ultraviolet spectrum and energy level assignments of Gd I in the 305–325nm region","authors":"Yun-Fei Li ,&nbsp;Jun-Yao Zhang ,&nbsp;Jing-Yi Xiong ,&nbsp;Kai-Chen Ma ,&nbsp;Li-De Wang ,&nbsp;Cai-Hua Zhu","doi":"10.1016/j.jqsrt.2025.109731","DOIUrl":"10.1016/j.jqsrt.2025.109731","url":null,"abstract":"<div><div>The ultraviolet spectrum of Gd I in the 305–325 nm range was studied using resonance ionization spectroscopy, revealing 196 transition lines, including 66 strong ones. The lower and upper energy levels were assigned to 190 lines by combining available reference data with pump–probe verification, 172 of which are reported for the first time. Seventeen new even-parity high-lying excited states were also identified. The strong lines reported here will contribute to future studies of Gd I Rydberg and autoionization states and enable two-color, two-step photoionization pathways for isotope separation and resonance ionization mass spectrometry analysis.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109731"},"PeriodicalIF":1.9,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145412039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “A practical guide to coding line-by-line trace gas absorption in Earth's atmosphere” [Journal of Quantitative Spectroscopy & Radiative Transfer 337 (2025) 109345]","authors":"S. Korkin ,&nbsp;A.M. Sayer ,&nbsp;A. Ibrahim ,&nbsp;A. Lyapustin","doi":"10.1016/j.jqsrt.2025.109713","DOIUrl":"10.1016/j.jqsrt.2025.109713","url":null,"abstract":"","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109713"},"PeriodicalIF":1.9,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145405045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning the electromagnetic density spectral function in a graphene–dielectric micro-cavity","authors":"Julieta Olivo ,&nbsp;Hernán Ferrari ,&nbsp;Jorge L. Blengino Albrieu ,&nbsp;Mauro Cuevas","doi":"10.1016/j.jqsrt.2025.109716","DOIUrl":"10.1016/j.jqsrt.2025.109716","url":null,"abstract":"<div><div>This work focuses on the study of the electromagnetic density spectral function (DSF) near a graphene–dielectric cavity. The cavity is formed in the space confined by the base of a dielectric micro-cube and a planar graphene sheet covering a dielectric substrate. The size and refractive index of the micro-cube, the constitutive parameters of graphene, and the gap between the dielectric cube and the graphene sheet determine the modifications to the DSF. We have developed a method based on the coupled dipole approximation (CDA), incorporating the surface Green’s tensor to account for the scattering processes with the graphene substrate, thereby rigorously modeling the electromagnetic problem. Our results reveal three well-distinguishable peaks in the DSF spectrum, which are attributed to the isolated micro-cube, the graphene substrate, and their mutual interaction. Specific parameters allow for the selective tuning of an individual peak’s properties, with minimal crosstalk to other spectral features. Using simple physical arguments related to the kinetic characteristics of surface plasmons (SPs) on graphene, we explain the key dependencies on constitutive and geometrical parameters.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109716"},"PeriodicalIF":1.9,"publicationDate":"2025-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical studies of allowed (E1) and forbidden (E2) transitions in Zr+29","authors":"S. Eser ,&nbsp;G. Günday Konan ,&nbsp;B. Karaçoban Usta ,&nbsp;İ. Gülsoy","doi":"10.1016/j.jqsrt.2025.109719","DOIUrl":"10.1016/j.jqsrt.2025.109719","url":null,"abstract":"<div><div>In this study, level energies, their radiative lifetimes and Landé <em>g</em>-factors, wavelengths, transition probabilities, weighted oscillator strengths and line strengths for electric dipole (E1) and electric quadrupole (E2) transitions of sodium-like zirconium (Zr<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>29</mn></mrow></msup></math></span>(Zr XXX), Z = 40) are determined. Four atomic codes are used in the calculations: the pseudo-relativistic Hartree–Fock code, including superposition of configurations with relativistic corrections (Cowan’s HFR method), the multiconfiguration Hartree–Fock (MCHF) method within the framework of Breit–Pauli relativistic corrections, the AUTOSTRUCTURE code, which includes Breit interactions and quantum electrodynamics contributions, and the general-purpose relativistic atomic structure package (GRASP) based on a fully relativistic multiconfiguration Dirac–Fock (MCDF) method. Our data set is compared with other results available in the literature. Furthermore, we present new atomic data for Zr<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>29</mn></mrow></msup></math></span>, which have not been published previously. The present results are reported as reference points for future calculations and measurements.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109719"},"PeriodicalIF":1.9,"publicationDate":"2025-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First high-resolution spectral study of the far infrared fundamental OH- torsional band of ethyl alcohol (CH3CH2OH), using synchrotron radiation","authors":"Indranath Mukhopadhyay","doi":"10.1016/j.jqsrt.2025.109707","DOIUrl":"10.1016/j.jqsrt.2025.109707","url":null,"abstract":"<div><div>In this work, the high-resolution far infrared (FIR) and infrared (IR) spectrum of ethyl alcohol has been recorded in the range 50–1200 cm^-1, with an excellent signal-to-noise (S/N) ratio, using a synchrotron radiation-based Fourier transform spectrometer. This spectrum, along with the spectrum obtained earlier with a conventional Fourier transform spectrometer in the range 15–350 cm^-1, has been utilized to assign many ∆<em>K</em>=±1 transitions from the trans- or anti and gauche-states in the ground state to connect the lowest lying state (o₂) for the first excited O<img>H torsional vibrational band. Since the transitions originating from the trans- states are the strongest mode, the terminating state is termed trans (anti) State (o₂). However, this state has odd parity. In addition, many millimeter (MMW) wave transitions have been measured elsewhere and assigned. The assignments have been rigorously confirmed using several complementary methods. An expanded appendix (Appendix-1) of about 8000 accurate wavenumbers of assigned transitions in the millimeter (MMW), FIR, and IR regions has been prepared and is being submitted as a depository. The assignments allowed indirect energy differences between the trans- and gauche states in the ground state, which are not otherwise obtainable via dipole selection rules. The accurate wavenumbers should help detect ethanol in interstellar space, particularly using the IR telescopes, and for further studies on intricate interactions between the various vibrational modes and rotation. This is the first time high-resolution studies have been performed in the elusive excited torsional state of ethyl alcohol. The reported transition wavenumber should have an uncertainty of less than ±0.0002 cm^-1</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"349 ","pages":"Article 109707"},"PeriodicalIF":1.9,"publicationDate":"2025-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparison of time-dependent Cloudy astrophysical code simulations with experimental X-ray spectra from keV laser-generated argon plasmas","authors":"N. Rathee ,&nbsp;F.P. Keenan ,&nbsp;R.J.R. Williams ,&nbsp;G.J. Ferland ,&nbsp;S.J. Rose ,&nbsp;S. White ,&nbsp;D. Riley","doi":"10.1016/j.jqsrt.2025.109720","DOIUrl":"10.1016/j.jqsrt.2025.109720","url":null,"abstract":"<div><div>We have generated strongly photoionized Ar plasmas in experiments designed to use primarily X-ray <span>l</span>-shell line emission generated from Ag foils irradiated by the VULCAN high-power laser at the UK Central Laser Facility. The principle of the experiment is that use of line emission rather than the usual sub-keV quasi-blackbody source allows keV radiation to play a more dominant role compared to softer X-rays and thus mimic the effect of a blackbody with a higher effective spectral temperature. Our aim is to reproduce in the laboratory the extreme photoionization conditions found in accretion-powered astrophysical sources. In this paper, we compare the experimental results on K-β X-ray Ar spectra with modelling using the time-dependent version of the Cloudy astrophysical code. The results indicate that photoionized laboratory plasmas can be successfully modelled with codes such as Cloudy that have been developed for application to astrophysical sources. Our comparison of simulation and experiment shows that the flux of sub-keV photons that photoionize the outer-shell electrons can have a significant effect, and that detailed measurements of the X-ray drive spectrum across all photon energy ranges are crucial for accurate modelling of experiments.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109720"},"PeriodicalIF":1.9,"publicationDate":"2025-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative infrared cross sections of vapor-phase perfluoroalkanoyl fluorides (C5 to C8)","authors":"Tracy J. Baker,&nbsp;Michael J. Wilhelm,&nbsp;Kendall D. Hughey,&nbsp;Kai-For Mo,&nbsp;Zoe M. Comstock,&nbsp;Timothy J. Johnson","doi":"10.1016/j.jqsrt.2025.109715","DOIUrl":"10.1016/j.jqsrt.2025.109715","url":null,"abstract":"<div><div>Quantitative infrared absorption cross sections for a series of four vapor-phase perfluoroalkanoyl fluorides at 50 °C are reported for the first time, namely the C5 to C8 homologues, perfluoropentanoyl fluoride (PFPeF), perfluorohexanoyl fluoride (PFHxF), perfluoroheptanoyl fluoride (PFHpF), and perfluorooctanoyl fluoride (PFOF). The integrated band strengths of the C-F bands centered near 1250 cm^-1 increase with chain length and represent some of the strongest infrared band strengths reported to date for any species, approximately 7 × 10^–3 (1/ppm-m) (2.7 × 10^–16 cm/molecule) for the perfluorooctanoyl fluoride. The perfluoroalkanoyl fluorides are also analyzed and the results interpreted via molecular modeling at the B3LYP/6–31G(d,p) level of theory. The DFT results revealed that while the data are indeed for pure species, the observed IR spectra need to be recognized as composite spectra of multiple conformers.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"348 ","pages":"Article 109715"},"PeriodicalIF":1.9,"publicationDate":"2025-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145396443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple analytical model for the reflection function of flat glacier ice surfaces and its application for optical remote sensing of glaciers","authors":"Alexander Kokhanovsky ,&nbsp;Lou-Anne Chevrollier ,&nbsp;Adrien Wehrlé ,&nbsp;Karl Segl ,&nbsp;Sabine Chabrillat","doi":"10.1016/j.jqsrt.2025.109717","DOIUrl":"10.1016/j.jqsrt.2025.109717","url":null,"abstract":"<div><div>We propose simple analytical equations for the modeling of clean and dusty flat glacier ice surfaces, which can be used to inversely derive the parameters of microstructure of flat bare glacier ice and snow using both ground – based and spaceborne observations of the hyperspectral solar reflectance. The retrievals are based on the asymptotic radiative transfer equations valid for the case of weak light absorption in the semi-infinite turbid medium. The light reflection at the air - ice and ice - air interfaces is fully accounted for. To demonstrate the validity of the approach, the derived equations are exemplarily applied to both ground – based and EnMAP satellite measurements over the Hardangerjøkulen glacier (Norway). A number of important parameters controlling spectral signatures of the snow and glacier ice surfaces have been derived. The ground-based measurements confirm that the theoretical formulation presented in this work can be used to represent the solar light spectral reflectivity of glaciers. The application to satellite hyperspectral imagery shows that this novel technique allows for the determination of the glacier ice albedo (spectral, broadband) based on spaceborne glacier ice reflectance measurement. Additionally, the results demonstrate that not spectrally neutral soot but rather deposited atmospheric dust which enhances the absorption towards UV is responsible for the light absorption by snow for the case studied. Spatial distribution maps of ice grain diameter and dust concentration are derived over the glacier. These findings show that the analytical theory presented in this work can support further research on the characterization and monitoring of glaciers based on current and upcoming hyperspectral remote sensing satellite missions.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"351 ","pages":"Article 109717"},"PeriodicalIF":1.9,"publicationDate":"2025-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}