Pub Date : 2025-02-28DOI: 10.1016/j.jqsrt.2025.109398
M. Alqadi, M. Telfah, A. Ibrahim, G. Alamat, H. Al-Khateeb, F. Alzoubi
The relative intensities and cross sections of L-shell X-ray fluorescence (XRF) for elements with atomic numbers and compounds containing some of these targeted elements were measured at two excitation energies, 21 keV and 25 keV, using a synchrotron radiation source at XSAFS/XRF beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East (SESAME), Jordan. The experimentally measured results of the relative intensities were compared to values obtained by the Fundamental Parameters’ method using two sets from literature, the calculated results based on the Dirac–Hartree–Slater model (DHS) by Puri (1993), and experimental data that are averaged and fitted by Campbell (2003). In this research, L-Shell XRF relative intensities and cross sections for the elements Gd, Er, Ta, W, Re, Tl and Bi and compounds and at excitation energies of 21 keV and 25 keV were measured.
{"title":"L-shell x-ray fluorescence relative intensities for elements with 64≤Z≤83 at 21 keV and 25 keV by synchrotron radiation","authors":"M. Alqadi, M. Telfah, A. Ibrahim, G. Alamat, H. Al-Khateeb, F. Alzoubi","doi":"10.1016/j.jqsrt.2025.109398","DOIUrl":"10.1016/j.jqsrt.2025.109398","url":null,"abstract":"<div><div>The relative intensities and cross sections of L-shell X-ray fluorescence (XRF) for elements with atomic numbers <span><math><mrow><mtext>64</mtext><mo>≤</mo><mi>Z</mi><mo>≤</mo><mtext>83</mtext></mrow></math></span> and compounds containing some of these targeted elements were measured at two excitation energies, 21 keV and 25 keV, using a synchrotron radiation source at XSAFS/XRF beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East (SESAME), Jordan. The experimentally measured results of the relative intensities were compared to values obtained by the Fundamental Parameters’ method using two sets from literature, the calculated results based on the Dirac–Hartree–Slater model (DHS) by Puri (1993), and experimental data that are averaged and fitted by Campbell (2003). In this research, L-Shell XRF relative intensities and cross sections for the elements Gd, Er, Ta, W, Re, Tl and Bi and compounds <span><math><mrow><msub><mrow><mi>GdN</mi></mrow><mrow><mn>3</mn></mrow></msub><msub><mrow><mi>O</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mi>Hg</mi></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mi>Cl</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> at excitation energies of 21 keV and 25 keV were measured.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"338 ","pages":"Article 109398"},"PeriodicalIF":2.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548722","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}
Pub Date : 2025-02-19DOI: 10.1016/j.jqsrt.2025.109397
Zhichang Fu , Siran Jia , Fuqiang Wang , Hao Yan , Ziming Cheng
Multispectral compatible stealth technologies are critically important in complex warfare environments, as they can effectively deceive various types of detection equipment, including visible light cameras and infrared thermal imagers. However, the integration of multiple stealth functionalities entails increasingly complex design requirements, posing significant challenges to the design of multispectral stealth structures. Herein, a metamaterial structure, composed of single-layer grating and multilayer films, are successfully designed to achieve visible-infrared stealth and efficient heat dissipation. This metamaterial supports visible stealth (0.38–0.78 μm), two–band infrared stealth for both 3–5 μm and 8–14 μm bands and enhances heat dissipation via two non-detection bands at 5–8 μm and 14–17 μm as well. This is demonstrated through the possibility of designing surfaces with different colors matching with background environment while simultaneously achieving minimal emissivity in the 3–5 μm and 8–14 μm bands (only 0.15 and 0.22, respectively) and significant emissivity in the non-detection bands at 5–8 μm and 14–17 μm (reaching 0.79 and 0.72, respectively). This research not only offers theoretical insights for designing metamaterial that combines visible–infrared stealth and heat dissipation but also provides valuable ideas and methodologies for the broader field of radiation regulation research.
{"title":"Multispectral stealth structures for simultaneous visible-infrared stealth and efficient heat dissipation","authors":"Zhichang Fu , Siran Jia , Fuqiang Wang , Hao Yan , Ziming Cheng","doi":"10.1016/j.jqsrt.2025.109397","DOIUrl":"10.1016/j.jqsrt.2025.109397","url":null,"abstract":"<div><div>Multispectral compatible stealth technologies are critically important in complex warfare environments, as they can effectively deceive various types of detection equipment, including visible light cameras and infrared thermal imagers. However, the integration of multiple stealth functionalities entails increasingly complex design requirements, posing significant challenges to the design of multispectral stealth structures. Herein, a metamaterial structure, composed of single-layer grating and multilayer films, are successfully designed to achieve visible-infrared stealth and efficient heat dissipation. This metamaterial supports visible stealth (0.38–0.78 μm), two–band infrared stealth for both 3–5 μm and 8–14 μm bands and enhances heat dissipation via two non-detection bands at 5–8 μm and 14–17 μm as well. This is demonstrated through the possibility of designing surfaces with different colors matching with background environment while simultaneously achieving minimal emissivity in the 3–5 μm and 8–14 μm bands (only 0.15 and 0.22, respectively) and significant emissivity in the non-detection bands at 5–8 μm and 14–17 μm (reaching 0.79 and 0.72, respectively). This research not only offers theoretical insights for designing metamaterial that combines visible–infrared stealth and heat dissipation but also provides valuable ideas and methodologies for the broader field of radiation regulation research.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109397"},"PeriodicalIF":2.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471254","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}
Pub Date : 2025-02-19DOI: 10.1016/j.jqsrt.2025.109382
Griffin A. Houston , Kevin K. Schwarm , Lance E. Christensen , R. Mitchell Spearrin
A laser absorption spectroscopy method was developed for in situ extraterrestrial sensing of four distinct water isotopologues near . Infrared rovibrational transitions for , , , and HDO were selected within the overlapping and fundamental bands to maximize relative absorption intensity and reduce spectral interference with neighboring water lines and other species, such as , while being positioned within the injection current tuning range of a single distributed-feedback diode laser held at one temperature. Temperature-dependent self-broadening parameters were measured from 296–375 K for the target lines via Voigt lineshape fitting of the transitions in the range of 3788.2–3789.9 cm−1 using vaporized water samples in a temperature- and pressure-controlled gas cell. Based on the novel wavelength selection and spectroscopic measurements, quantitative, calibration-free sensing of isotope abundance ratios of D/H, , and in water vapor was demonstrated in a portable form-factor device using a diode laser, compact Herriott cell, and a liquid water injection system. Accuracy and detection limits using scanned-wavelength direct absorption were estimated by comparison to water samples of known isotopic abundance.
{"title":"Water isotope spectroscopy near 2.6μm for D/H, 18O/16O, and 17O/16O analysis in planetary bodies","authors":"Griffin A. Houston , Kevin K. Schwarm , Lance E. Christensen , R. Mitchell Spearrin","doi":"10.1016/j.jqsrt.2025.109382","DOIUrl":"10.1016/j.jqsrt.2025.109382","url":null,"abstract":"<div><div>A laser absorption spectroscopy method was developed for in situ extraterrestrial sensing of four distinct water isotopologues near <span><math><mrow><mn>2</mn><mo>.</mo><mn>64</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>. Infrared rovibrational transitions for <span><math><mrow><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mn>16</mn></mrow></msubsup><mi>O</mi></mrow></math></span>, <span><math><mrow><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mn>18</mn></mrow></msubsup><mi>O</mi></mrow></math></span>, <span><math><mrow><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mn>17</mn></mrow></msubsup><mi>O</mi></mrow></math></span>, and HDO were selected within the overlapping <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> fundamental bands to maximize relative absorption intensity and reduce spectral interference with neighboring water lines and other species, such as <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>, while being positioned within the injection current tuning range of a single distributed-feedback diode laser held at one temperature. Temperature-dependent self-broadening parameters were measured from 296–375 K for the target lines via Voigt lineshape fitting of the transitions in the range of 3788.2–3789.9 cm<sup>−1</sup> using vaporized water samples in a temperature- and pressure-controlled gas cell. Based on the novel wavelength selection and spectroscopic measurements, quantitative, calibration-free sensing of isotope abundance ratios of D/H, <span><math><mrow><msup><mrow></mrow><mrow><mn>18</mn></mrow></msup><mi>O</mi><msup><mrow><mo>/</mo></mrow><mrow><mn>16</mn></mrow></msup><mi>O</mi></mrow></math></span>, and <span><math><mrow><msup><mrow></mrow><mrow><mn>17</mn></mrow></msup><mi>O</mi><msup><mrow><mo>/</mo></mrow><mrow><mn>16</mn></mrow></msup><mi>O</mi></mrow></math></span> in water vapor was demonstrated in a portable form-factor device using a diode laser, compact Herriott cell, and a liquid water injection system. Accuracy and detection limits using scanned-wavelength direct absorption were estimated by comparison to water samples of known isotopic abundance.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109382"},"PeriodicalIF":2.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-14DOI: 10.1016/j.jqsrt.2025.109394
Miao Wu , Zhencen He
The energy levels, transition probabilities, the relative uncertainty u, and wavelengths of electric dipole (E1) transitions for Ga-like Ag, Cd, and In ions were produced using the general purpose relativistic atomic structure package (GRASP2K) based on the fully relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) method. The calculated energy levels and wavelengths are in excellent agreement with experimental and theoretical values. On the basis of the calculations, the energy levels of the highly excited states, the wavelengths and transition probabilities of E1 transitions (4s24p-4s24d, 4s4p2–4p3) are also given, which are new and previously unpublished.
{"title":"Energy levels, transition probabilities, and wavelengths for Ga-like Ag, Cd, and In ions","authors":"Miao Wu , Zhencen He","doi":"10.1016/j.jqsrt.2025.109394","DOIUrl":"10.1016/j.jqsrt.2025.109394","url":null,"abstract":"<div><div>The energy levels, transition probabilities, the relative uncertainty u, and wavelengths of electric dipole (E1) transitions for Ga-like Ag, Cd, and In ions were produced using the general purpose relativistic atomic structure package (GRASP2K) based on the fully relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) method. The calculated energy levels and wavelengths are in excellent agreement with experimental and theoretical values. On the basis of the calculations, the energy levels of the highly excited states, the wavelengths and transition probabilities of E1 transitions (4s<sup>2</sup>4p-4s<sup>2</sup>4d, 4s4p<sup>2</sup>–4p<sup>3</sup>) are also given, which are new and previously unpublished.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109394"},"PeriodicalIF":2.3,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453151","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}
Pub Date : 2025-02-12DOI: 10.1016/j.jqsrt.2025.109393
K. Amari , A. Kahoul , J.M. Sampaio , Y. Kasri , J.P. Marques , F. Parente , A. Hamidani , S. Croft , A. Favalli , S. Daoudi , A. Zidi , B. Berkani
In this study, empirical and semi-empirical X-ray fluorescence cross-sections are generated for , , and lines. The approach used was the fitting of experimental data by three-dimensional formulae. The empirical values were obtained through a fitting method making use of a three-dimensional function against atomic number Z and excitation energy E, resulting in a three-dimensional plot allowing to estimate empirically , , , and X-ray fluorescence cross sections. Further, new semi-empirical values were derived by fitting the weighted average values using an analytical function against atomic number Z and energy E, and subsequently the ratio is fitted by a three-dimensional analyzing polynomial function as a function of Z and energy E. For and lines the range of atomic numbers covered was whereas for and it was Our findings were compared with selected experimental results, and good agreement was obtained.
{"title":"Compilation of empirical and semi-empirical Kα1, Kα2, Kβ1′, and Kβ2′ X-ray fluorescence cross-sections by the application of fitting approaches","authors":"K. Amari , A. Kahoul , J.M. Sampaio , Y. Kasri , J.P. Marques , F. Parente , A. Hamidani , S. Croft , A. Favalli , S. Daoudi , A. Zidi , B. Berkani","doi":"10.1016/j.jqsrt.2025.109393","DOIUrl":"10.1016/j.jqsrt.2025.109393","url":null,"abstract":"<div><div>In this study, empirical and semi-empirical X-ray fluorescence cross-sections are generated for <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>1</mn></msub></mrow></math></span>, <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>2</mn></msub></mrow></math></span>, <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>1</mn><mo>′</mo></msubsup><mo>,</mo><mspace></mspace></mrow></math></span>and <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>2</mn><mo>′</mo></msubsup><mspace></mspace></mrow></math></span>lines. The approach used was the fitting of experimental data by three-dimensional formulae. The empirical values were obtained through a fitting method making use of a three-dimensional function against atomic number <em>Z</em> and excitation energy <em>E</em>, resulting in a three-dimensional plot allowing to estimate empirically <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>1</mn></msub></mrow></math></span>, <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>2</mn></msub></mrow></math></span>, <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>1</mn><mo>′</mo></msubsup></mrow></math></span>, and <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>2</mn><mo>′</mo></msubsup><mspace></mspace></mrow></math></span>X-ray fluorescence cross sections. Further, new semi-empirical values were derived by fitting the weighted average values using an analytical function against atomic number <em>Z</em> and energy <em>E</em>, and subsequently the ratio <span><math><mrow><msub><mi>S</mi><mi>W</mi></msub><mo>=</mo><msub><mrow><mo>(</mo><msub><mi>σ</mi><msub><mi>K</mi><mi>i</mi></msub></msub><mo>)</mo></mrow><mtext>exp</mtext></msub><mo>/</mo><msub><mrow><mo>(</mo><msub><mi>σ</mi><msub><mi>K</mi><mi>i</mi></msub></msub><mo>)</mo></mrow><mi>W</mi></msub><mspace></mspace></mrow></math></span>is fitted by a three-dimensional analyzing polynomial function as a function of <em>Z</em> and energy <em>E</em>. For <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>1</mn></msub></mrow></math></span> and <span><math><mrow><mi>K</mi><msub><mi>α</mi><mn>2</mn></msub></mrow></math></span> lines the range of atomic numbers covered was <span><math><mrow><mn>52</mn><mo>≤</mo><mi>Z</mi><mo>≤</mo><mn>92</mn></mrow></math></span> whereas for <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>1</mn><mo>′</mo></msubsup></mrow></math></span> and <span><math><mrow><mi>K</mi><mi>β</mi><msubsup><mrow></mrow><mn>2</mn><mo>′</mo></msubsup></mrow></math></span> it was<span><math><mrow><mspace></mspace><mn>57</mn><mo>≤</mo><mi>Z</mi><mo>≤</mo><mn>79</mn><mo>.</mo></mrow></math></span> Our findings were compared with selected experimental results, and good agreement was obtained.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109393"},"PeriodicalIF":2.3,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453150","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}
Line shape of the first rotational transition of the CO molecule perturbed by N collisions was studied beyond the traditional Voigt profile at pressures from 0.1 up to 1500 Torr and temperatures from 238 up to 353 K using two different spectrometers with complementary abilities. Line intensity, shifting, mixing, broadening, and underlying continuum coefficients were retrieved. The experimental speed dependence (SD) broadening parameters and their temperature dependence were compared to the results of the recent quantum scattering calculations showing fair agreement yet pointing to possible necessity of improvement of the theoretical approach to the CO–N collisional system.
{"title":"Collisional parameters of the pure rotational R(0) line of CO in N2: Experiment versus theory","authors":"D.S. Makarov, I.N. Vilkov, T.A. Galanina, E.A. Serov, M.A. Koshelev, M.Yu. Tretyakov","doi":"10.1016/j.jqsrt.2025.109379","DOIUrl":"10.1016/j.jqsrt.2025.109379","url":null,"abstract":"<div><div>Line shape of the first rotational transition of the CO molecule perturbed by N<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> collisions was studied beyond the traditional Voigt profile at pressures from 0.1 up to 1500 Torr and temperatures from 238 up to 353 K using two different spectrometers with complementary abilities. Line intensity, shifting, mixing, broadening, and underlying continuum coefficients were retrieved. The experimental speed dependence (SD) broadening parameters and their temperature dependence were compared to the results of the recent quantum scattering calculations showing fair agreement yet pointing to possible necessity of improvement of the theoretical approach to the CO–N<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> collisional system.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109379"},"PeriodicalIF":2.3,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394889","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}
Pub Date : 2025-02-06DOI: 10.1016/j.jqsrt.2025.109380
Patrick Stegmann , Benjamin Johnson , Isaac Moradi , Bryan Karpowicz , Will McCarty , Haixia Liu , Suryakanti Dutta , Thomas Auligné
The CRTM transmittance coefficient generation package is a high-performance computing workflow to generate spectral and transmittance coefficients for the JCSDA Community Radiative Transfer Model (CRTM), which is used as an observation operator in satellite data assimilation applications. The characteristics of new instruments, whose observations are modeled by the CRTM, are encapsulated in these aforementioned coefficient data structures. This approach is a key factor in achieving the necessary high computational speeds with the CRTM. Complex atmospheric transmittance spectra in particular are approximated using the ODPS and ODAS algorithms. The transmittance coefficient generation package for the first time provides a unified and reproducible workflow to CRTM generate coefficients.
{"title":"The CRTM transmittance coefficient package","authors":"Patrick Stegmann , Benjamin Johnson , Isaac Moradi , Bryan Karpowicz , Will McCarty , Haixia Liu , Suryakanti Dutta , Thomas Auligné","doi":"10.1016/j.jqsrt.2025.109380","DOIUrl":"10.1016/j.jqsrt.2025.109380","url":null,"abstract":"<div><div>The CRTM transmittance coefficient generation package is a high-performance computing workflow to generate spectral and transmittance coefficients for the JCSDA Community Radiative Transfer Model (CRTM), which is used as an observation operator in satellite data assimilation applications. The characteristics of new instruments, whose observations are modeled by the CRTM, are encapsulated in these aforementioned coefficient data structures. This approach is a key factor in achieving the necessary high computational speeds with the CRTM. Complex atmospheric transmittance spectra in particular are approximated using the ODPS and ODAS algorithms. The transmittance coefficient generation package for the first time provides a unified and reproducible workflow to CRTM generate coefficients.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"336 ","pages":"Article 109380"},"PeriodicalIF":2.3,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-06DOI: 10.1016/j.jqsrt.2025.109381
Geyi Su, Minglei Guan, Mingxu Su
A scattering model based on the Monte Carlo method (MCM) is developed to investigate the light scattering and extinction characteristics of non-aligned laser beams incident on a high concentration of mixed particle system. A set of measurement test systems for acquiring the scattered light energy distribution is constructed to verify the model accuracy, which yields the maximum root mean square errors (RMSE) among the MCM and the conventional model and the experimental results of 0.006 and 0.011, respectively. Subsequently, the differential evolution (DE) algorithm is introduced to deduce the particle size distribution based on the spectral content. The inversion results indicate that the MCM model can effectively correct the measurement errors caused by the non-aligned incident beams and multiple scattering effects due to high concentrations. Thus, the absolute relative errors compared with the reference values have been reduced from 33.08 % and 10.60 % for the conventional model to within 3.00 %. Additionally, three distinct sizes and mixing ratios of the mixed particle system have been successfully inverted with maximum absolute relative errors of 8.31 %, 3.14 %, and 5.41 %.
{"title":"Laser diffraction modeling based on laser and particle behaviour statistics for particle size characterization","authors":"Geyi Su, Minglei Guan, Mingxu Su","doi":"10.1016/j.jqsrt.2025.109381","DOIUrl":"10.1016/j.jqsrt.2025.109381","url":null,"abstract":"<div><div>A scattering model based on the Monte Carlo method (MCM) is developed to investigate the light scattering and extinction characteristics of non-aligned laser beams incident on a high concentration of mixed particle system. A set of measurement test systems for acquiring the scattered light energy distribution is constructed to verify the model accuracy, which yields the maximum root mean square errors (RMSE) among the MCM and the conventional model and the experimental results of 0.006 and 0.011, respectively. Subsequently, the differential evolution (DE) algorithm is introduced to deduce the particle size distribution based on the spectral content. The inversion results indicate that the MCM model can effectively correct the measurement errors caused by the non-aligned incident beams and multiple scattering effects due to high concentrations. Thus, the absolute relative errors compared with the reference values have been reduced from 33.08 % and 10.60 % for the conventional model to within 3.00 %. Additionally, three distinct sizes and mixing ratios of the mixed particle system have been successfully inverted with maximum absolute relative errors of 8.31 %, 3.14 %, and 5.41 %.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"337 ","pages":"Article 109381"},"PeriodicalIF":2.3,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419311","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}
The high resolution submillimeter wave spectrum of the 12CH235Cl2 methylene chloride was analyzed in the wide spectral region from 0.075 up to 1.090 THz. The 5451 lines with the maximum values of quantum number and , which correspond to 4037 unresolved singlet and central lines of triplets and 1414 peripheral lines of triplets (this spectroscopic structure is due to partially resolved/unresolved Cl quadrupole coupling hyperfine structure), were assigned in the experimental spectra to the transitions of the vibrational state. Weighted fit of the rotational and centrifugal distortion parameters of the Watson Hamiltonian in reduction and representation, as well as of the Cl quadrupole coupling constants was made with the SPFIT/SPCAT package of Pickett. The obtained set of twenty rotational and centrifugal distortion parameters and three quadrupole coupling parameters reproduces values of the 4037 experimental multiplet centra with the kHz and of the 1414 experimental peripheral lines of triplets with the kHz. Comparison with the rotational and centrifugal distortion parameters of the vibrational state known in the literature was made and shown that the parameters known in the literature reproduce the same set of experimental data with an accuracy in 150–300 times worse in comparison with the results of the present study. At the same time, the obtained values of the quadrupole coupling parameters show an excellent correspondence with the values of corresponding parameters recently obtained by Z. Kisiel (J Mol Spectrosc 2024; 406:111954).
{"title":"Submillimeter wave spectrum of the 12CH235Cl2 methylene chloride in the excited (v4=1) vibrational state up to 1.1 THz","authors":"O.N. Ulenikov , O.V. Gromova , E.S. Bekhtereva , Yu.V. Khudyakova , V.L. Vaks","doi":"10.1016/j.jqsrt.2025.109377","DOIUrl":"10.1016/j.jqsrt.2025.109377","url":null,"abstract":"<div><div>The high resolution submillimeter wave spectrum of the <sup>12</sup>CH<sub>2</sub><sup>35</sup>Cl<sub>2</sub> methylene chloride was analyzed in the wide spectral region from 0.075 up to 1.090 THz. The 5451 lines with the maximum values of quantum number <span><math><mrow><msup><mrow><mi>J</mi></mrow><mrow><mtext>max</mtext></mrow></msup><mo>=</mo><mn>98</mn></mrow></math></span> and <span><math><mrow><msubsup><mrow><mi>K</mi></mrow><mrow><mi>a</mi></mrow><mrow><mtext>max</mtext></mrow></msubsup><mo>=</mo><mn>24</mn></mrow></math></span>, which correspond to 4037 unresolved singlet and central lines of triplets and 1414 peripheral lines of triplets (this spectroscopic structure is due to partially resolved/unresolved Cl quadrupole coupling hyperfine structure), were assigned in the experimental spectra to the transitions of the <span><math><mrow><mo>(</mo><msub><mrow><mi>v</mi></mrow><mrow><mn>4</mn></mrow></msub><mo>=</mo><mn>1</mn><mo>)</mo></mrow></math></span> vibrational state. Weighted fit of the rotational and centrifugal distortion parameters of the Watson Hamiltonian in <span><math><mrow><mi>A</mi><mo>−</mo></mrow></math></span>reduction and <span><math><mrow><msup><mrow><mi>I</mi></mrow><mrow><mi>r</mi></mrow></msup><mo>−</mo></mrow></math></span> representation, as well as of the Cl quadrupole coupling constants was made with the SPFIT/SPCAT package of Pickett. The obtained set of twenty rotational and centrifugal distortion parameters and three quadrupole coupling parameters reproduces values of the 4037 experimental multiplet centra with the <span><math><mrow><msub><mrow><mi>d</mi></mrow><mrow><mtext>rms</mtext></mrow></msub><mo>=</mo><mn>14</mn></mrow></math></span> kHz and of the 1414 experimental peripheral lines of triplets with the <span><math><mrow><msub><mrow><mi>d</mi></mrow><mrow><mtext>rms</mtext></mrow></msub><mo>=</mo><mn>34</mn></mrow></math></span> kHz. Comparison with the rotational and centrifugal distortion parameters of the <span><math><mrow><mo>(</mo><msub><mrow><mi>v</mi></mrow><mrow><mn>4</mn></mrow></msub><mo>=</mo><mn>1</mn><mo>)</mo></mrow></math></span> vibrational state known in the literature was made and shown that the parameters known in the literature reproduce the same set of experimental data with an accuracy in 150–300 times worse in comparison with the results of the present study. At the same time, the obtained values of the quadrupole coupling <span><math><mrow><mi>χ</mi><mo>−</mo></mrow></math></span>parameters show an excellent correspondence with the values of corresponding parameters recently obtained by Z. Kisiel (J Mol Spectrosc 2024; 406:111954).</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"336 ","pages":"Article 109377"},"PeriodicalIF":2.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377211","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}
Pub Date : 2025-02-01DOI: 10.1016/j.jqsrt.2025.109375
D. Stefańska , S. Mieloch , J. Ruczkowski , M. Klempka , B. Furmann , M. Elantkowska , P. Głowacki
In this work a preliminary feasibility study of the possibilities of laser cooling for the terbium atom was performed. Possible first- and second-stage cooling transitions were considered. For each of them semi-empirical estimation of the branching ratios and the lifetimes of the upper levels was performed. These should be regarded as rough estimates only, and certainly require experimental verification (planned in the future). The spectral lines proposed for possible second-stage cooling transitions were recorded by laser spectroscopy in a hollow cathode discharge lamp to confirm their hyperfine structure patterns and verify the hitherto known values of the constants and . Suitable hyperfine structure components for cooling and hyperfine repumping were indicated. A possible application of two of the transitions considered for a system for electromagnetically induced transparency, based on the hyperfine structure, is also suggested.
{"title":"Search for the laser-cooling schemes in the terbium atom","authors":"D. Stefańska , S. Mieloch , J. Ruczkowski , M. Klempka , B. Furmann , M. Elantkowska , P. Głowacki","doi":"10.1016/j.jqsrt.2025.109375","DOIUrl":"10.1016/j.jqsrt.2025.109375","url":null,"abstract":"<div><div>In this work a preliminary feasibility study of the possibilities of laser cooling for the terbium atom was performed. Possible first- and second-stage cooling transitions were considered. For each of them semi-empirical estimation of the branching ratios and the lifetimes of the upper levels was performed. These should be regarded as rough estimates only, and certainly require experimental verification (planned in the future). The spectral lines proposed for possible second-stage cooling transitions were recorded by laser spectroscopy in a hollow cathode discharge lamp to confirm their hyperfine structure patterns and verify the hitherto known values of the constants <span><math><mi>A</mi></math></span> and <span><math><mi>B</mi></math></span>. Suitable hyperfine structure components for cooling and hyperfine repumping were indicated. A possible application of two of the transitions considered for a <span><math><mi>Λ</mi></math></span> system for electromagnetically induced transparency, based on the hyperfine structure, is also suggested.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"335 ","pages":"Article 109375"},"PeriodicalIF":2.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351176","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}
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