Pub Date : 2024-10-05DOI: 10.1016/j.jqsrt.2024.109213
Nils Madenach, Rene Preusker, Nicole Docter, Lena Jänicke, Jürgen Fischer
Radiative transfer simulations (RTS) still face significant challenges in accurately representing the highly complex gas absorption spectra of the Earth’s atmosphere. Line-by-line RTS achieves high accuracy by solving radiative transfer equations for narrow spectral intervals, but at a considerable computational cost. Especially in remote sensing and climate modeling, a trade-off between efficiency and accuracy must be done. k-distribution methods are widespread in the scientific community and offer a way to make this trade-off. k-distribution methods reorder the absorption spectra for a given spectral interval and find appropriate so-called k-bins. In the k-space much less integration points can be used, while maintaining high accuracy. The way to find optimal k-bins differs from method to method and depends on the application. In this paper, we present the flexible and fast k-bin tool. The python based lightweight k-bin tool provides a variety of different k-distribution methods and configuration options. One k-distribution method is the in-house developed k-bin approach. The different setups of the tool can be easily compared, helping to decide which method and configuration is best suited for a given application. We encourage the user of the tool to continue to optimize the k-bin tool and to extend it with new approaches and functionalities.
辐射传递模拟（RTS）在准确表示地球大气高度复杂的气体吸收光谱方面仍然面临巨大挑战。逐行辐射传递模拟通过求解窄光谱区间的辐射传递方程来实现高精度，但计算成本相当高。特别是在遥感和气候建模中，必须在效率和精度之间进行权衡。k 分布方法在科学界非常普遍，它提供了一种权衡方法。在 k 空间中，可以使用更少的积分点，同时保持较高的精度。寻找最佳 k-bins 的方法因方法而异，并取决于应用。在本文中，我们介绍了灵活快速的 k-bin 工具。这个基于 python 的轻量级 k-bin 工具提供了多种不同的 k 分布方法和配置选项。其中一种 k 分布方法是内部开发的 k-bin 方法。该工具的不同设置可以很容易地进行比较，有助于决定哪种方法和配置最适合特定应用。我们鼓励该工具的用户继续优化 k-bin 工具，并通过新的方法和功能对其进行扩展。
{"title":"The k-bin tool: Fast and flexible k-distribution algorithms written in Python","authors":"Nils Madenach, Rene Preusker, Nicole Docter, Lena Jänicke, Jürgen Fischer","doi":"10.1016/j.jqsrt.2024.109213","DOIUrl":"10.1016/j.jqsrt.2024.109213","url":null,"abstract":"<div><div>Radiative transfer simulations (RTS) still face significant challenges in accurately representing the highly complex gas absorption spectra of the Earth’s atmosphere. Line-by-line RTS achieves high accuracy by solving radiative transfer equations for narrow spectral intervals, but at a considerable computational cost. Especially in remote sensing and climate modeling, a trade-off between efficiency and accuracy must be done. k-distribution methods are widespread in the scientific community and offer a way to make this trade-off. k-distribution methods reorder the absorption spectra <span><math><mi>k</mi></math></span> for a given spectral interval and find appropriate so-called k-bins. In the k-space much less integration points can be used, while maintaining high accuracy. The way to find optimal k-bins differs from method to method and depends on the application. In this paper, we present the flexible and fast k-bin tool. The python based lightweight k-bin tool provides a variety of different k-distribution methods and configuration options. One k-distribution method is the in-house developed k-bin approach. The different setups of the tool can be easily compared, helping to decide which method and configuration is best suited for a given application. We encourage the user of the tool to continue to optimize the k-bin tool and to extend it with new approaches and functionalities.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109213"},"PeriodicalIF":2.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423843","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}
Colored photovoltaic (PV) modules with integrated disordered coatings exhibit attractive potential for generating renewable electricity. However, most existing studies on these modules rely on the assumption that the disordered coatings are random systems, neglecting the effects of spatial correlation. In this work, we thoroughly investigate the effects of spatial correlation on the color properties and performance of colored PV modules with integrated disordered coatings, using the full-wave electromagnetic simulation techniques. Our findings indicate that increasing the degree of spatial correlation results in a sharper and narrower reflectance peak, while having a negligible impact on the peak position. This trend suggests that the spatial correlation offers an alternative strategy for producing more vivid color, although it is less effective in expanding the color range. On the other hand, the spatial correlation has little impact on the power conversion efficiency (PCE) of PV modules. Therefore, it is feasible to produce colored PV modules with more vivid colors without significantly affecting the PCE by simply adjusting the degree of spatial correlation.
{"title":"Role of spatial correlation on the performance of colored photovoltaic modules with integrate disordered media","authors":"Jinan Zhai , Shangyu Zhang , Chong Zheng , Jiyun Tang , Linhua Liu","doi":"10.1016/j.jqsrt.2024.109216","DOIUrl":"10.1016/j.jqsrt.2024.109216","url":null,"abstract":"<div><div>Colored photovoltaic (PV) modules with integrated disordered coatings exhibit attractive potential for generating renewable electricity. However, most existing studies on these modules rely on the assumption that the disordered coatings are random systems, neglecting the effects of spatial correlation. In this work, we thoroughly investigate the effects of spatial correlation on the color properties and performance of colored PV modules with integrated disordered coatings, using the full-wave electromagnetic simulation techniques. Our findings indicate that increasing the degree of spatial correlation results in a sharper and narrower reflectance peak, while having a negligible impact on the peak position. This trend suggests that the spatial correlation offers an alternative strategy for producing more vivid color, although it is less effective in expanding the color range. On the other hand, the spatial correlation has little impact on the power conversion efficiency (PCE) of PV modules. Therefore, it is feasible to produce colored PV modules with more vivid colors without significantly affecting the PCE by simply adjusting the degree of spatial correlation.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109216"},"PeriodicalIF":2.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423824","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 : 2024-10-05DOI: 10.1016/j.jqsrt.2024.109211
Carmine Serio , Guido Masiello , Giuliano Liuzzi , Angela Cersosimo , Tiziano Maestri , Michele Martinazzo , Fabrizio Masin , Giorgia Proietti Pelliccia , Sara Venafra , Claude Camy-Peyret
Based on a recently developed all-sky forward model (σ-IASI/F2N) for the computation of spectral radiances in the range 100 to 2760 cm-1, the paper addresses the spring onset of the Antarctica ozone hole with infrared observations from the IASI (Infrared Atmospheric Sounder Interferometer) satellite sounder. The Antarctica ozone hole is a cyclic event that grows in normal conditions in late August and collapses in late November/early December. Because of climate change (cooling of the stratosphere), the O3 hole is expected to become deeper. Indeed, 2021 and 2023 have been characterized by very spatially extensive and deep ozone hole. To demonstrate that we can gain further insights into these phenomena with the help of infrared nadir viewing observations, we have developed an all-sky retrieval tool, which inverts the whole IASI infrared spectrum to simultaneously estimate thermodynamic and geophysical parameters, including ozone and nitric acid, which are key parameters in analyzing the Antarctic ozone hole. Infrared sounders acquire data day and night, unlike visible and ultraviolet sounders, which are only operational during daytime. This enables us to acquire data also during the polar night, which is a critical time for O3 hole formation. Ice polar stratospheric clouds have been identified and fitted with our scheme. Maps of atmospheric ozone, complemented with those of nitric acid, temperature, and lower stratosphere height, have been retrieved for July, September, and October 2021 and 2023. Results are compared to those derived from TROPOMI (TROPOspheric Monitoring Instrument) and OMI (Ozone Monitoring Instrument), showing a very good agreement. The comparison of simultaneously retrieved O3 and HNO3 shows that the onset of the ozone hole is associated with relevant denitrification in the Antarctica Stratosphere. For 2023, our findings also show that O3 depletion episodes began as early as July. Although demonstrative, our analysis evidences the importance of Numerical Weather Prediction centers to assimilating all-sky infrared radiances (day, night, clear, or with ice or water clouds) to get insights into providing a more comprehensive picture of the Southern Spring ozone depletion over Antarctica.
{"title":"Demonstration of a physical inversion scheme for all-sky, day-night IASI observations and application to the analysis of the onset of the Antarctica ozone hole: Assessment of retrievals and consistency of forward modeling","authors":"Carmine Serio , Guido Masiello , Giuliano Liuzzi , Angela Cersosimo , Tiziano Maestri , Michele Martinazzo , Fabrizio Masin , Giorgia Proietti Pelliccia , Sara Venafra , Claude Camy-Peyret","doi":"10.1016/j.jqsrt.2024.109211","DOIUrl":"10.1016/j.jqsrt.2024.109211","url":null,"abstract":"<div><div>Based on a recently developed all-sky forward model (σ-IASI/F2N) for the computation of spectral radiances in the range 100 to 2760 cm<sup>-1</sup>, the paper addresses the spring onset of the Antarctica ozone hole with infrared observations from the IASI (Infrared Atmospheric Sounder Interferometer) satellite sounder. The Antarctica ozone hole is a cyclic event that grows in normal conditions in late August and collapses in late November/early December. Because of climate change (cooling of the stratosphere), the O<sub>3</sub> hole is expected to become deeper. Indeed, 2021 and 2023 have been characterized by very spatially extensive and deep ozone hole. To demonstrate that we can gain further insights into these phenomena with the help of infrared nadir viewing observations, we have developed an all-sky retrieval tool, which inverts the whole IASI infrared spectrum to simultaneously estimate thermodynamic and geophysical parameters, including ozone and nitric acid, which are key parameters in analyzing the Antarctic ozone hole. Infrared sounders acquire data day and night, unlike visible and ultraviolet sounders, which are only operational during daytime. This enables us to acquire data also during the polar night, which is a critical time for O<sub>3</sub> hole formation. Ice polar stratospheric clouds have been identified and fitted with our scheme. Maps of atmospheric ozone, complemented with those of nitric acid, temperature, and lower stratosphere height, have been retrieved for July, September, and October 2021 and 2023. Results are compared to those derived from TROPOMI (TROPOspheric Monitoring Instrument) and OMI (Ozone Monitoring Instrument), showing a very good agreement. The comparison of simultaneously retrieved O<sub>3</sub> and HNO<sub>3</sub> shows that the onset of the ozone hole is associated with relevant denitrification in the Antarctica Stratosphere. For 2023, our findings also show that O<sub>3</sub> depletion episodes began as early as July. Although demonstrative, our analysis evidences the importance of Numerical Weather Prediction centers to assimilating all-sky infrared radiances (day, night, clear, or with ice or water clouds) to get insights into providing a more comprehensive picture of the Southern Spring ozone depletion over Antarctica.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109211"},"PeriodicalIF":2.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423841","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 : 2024-10-02DOI: 10.1016/j.jqsrt.2024.109208
Hang Wang , Md Ershadul Haque , Reza Abedi , Saba Mudaliar
A space-angle discontinuous Galerkin (saDG) method is used to solve the steady-state radiative transfer equation (RTE) for 2D problems involving absorption, emission, and scattering for a semitransparent medium. This approach discretizes both spatial and angular domains. Parallel computing is based on angular decomposition (AD), and domain decomposition (DD) techniques. The DD technique directly solves the entire domain using the MUMPS library, whereas the AD technique results in an iterative approach for scattering media. This study proposes a novel hybrid AD-DD method, combining the best aspects of both techniques. Numerical results investigate the scalability, performance, and efficiency of AD and DD techniques. It is shown that a hybrid AD-DD technique is superior to these individual techniques by taking advantage of their strengths. Numerical methods demonstrate the applicability of the method of the best combination of hybrid AD-DD to 2D scattering gray media with complex geometries or enclosures with circular and square obstacles.
采用空间-角度非连续伽勒金（saDG）方法求解稳态辐射传递方程（RTE），以解决半透明介质的吸收、发射和散射等二维问题。这种方法对空间域和角度域都进行了离散处理。并行计算基于角分解（AD）和域分解（DD）技术。DD 技术使用 MUMPS 库直接求解整个域，而 AD 技术则是针对散射介质的迭代方法。本研究提出了一种新颖的 AD-DD 混合方法，结合了两种技术的优点。数值结果研究了 AD 和 DD 技术的可扩展性、性能和效率。结果表明，AD-DD 混合技术利用了这两种技术的优势，优于单独的技术。数值方法证明了混合 AD-DD 最佳组合方法适用于具有复杂几何形状或具有圆形和方形障碍物的二维散射灰色介质。
{"title":"Integrating angular and domain decomposition with space-angle discontinuous Galerkin methods in 2D radiative transfer","authors":"Hang Wang , Md Ershadul Haque , Reza Abedi , Saba Mudaliar","doi":"10.1016/j.jqsrt.2024.109208","DOIUrl":"10.1016/j.jqsrt.2024.109208","url":null,"abstract":"<div><div>A space-angle discontinuous Galerkin (saDG) method is used to solve the steady-state radiative transfer equation (RTE) for 2D problems involving absorption, emission, and scattering for a semitransparent medium. This approach discretizes both spatial and angular domains. Parallel computing is based on angular decomposition (AD), and domain decomposition (DD) techniques. The DD technique directly solves the entire domain using the MUMPS library, whereas the AD technique results in an iterative approach for scattering media. This study proposes a novel hybrid AD-DD method, combining the best aspects of both techniques. Numerical results investigate the scalability, performance, and efficiency of AD and DD techniques. It is shown that a hybrid AD-DD technique is superior to these individual techniques by taking advantage of their strengths. Numerical methods demonstrate the applicability of the method of the best combination of hybrid AD-DD to 2D scattering gray media with complex geometries or enclosures with circular and square obstacles.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109208"},"PeriodicalIF":2.3,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423848","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 : 2024-10-01DOI: 10.1016/j.jqsrt.2024.109202
Matthias Koch , Stefan Pielsticker , Jochen Ströhle , Reinhold Kneer
The index of refraction (IOR) is required to model thermal radiation interaction with pulverized solid fuels. In this work, the complex index of refraction of biomass (walnut shell) is therefore determined using pulverized particles. Single particles are irradiated, and the scattered radiation is measured in different directions. To avoid falsification of the scattering pattern (phase function), the particles are kept contactless in an acoustic levitator. Here, over 1000 different phase functions are measured. The measured scattering patterns are evaluated using an inverse evaluation procedure to determine the IOR. Mie theory serves as the basis for the mathematical modeling of the radiation properties of the particles. The measured IOR is then compared to data from the literature on coal. For the wavelength range no distinct differences are noticed between the coal and biomass IOR. For the real part of the biomass IOR is larger and the differences increase with increasing wavelength. However, the order of magnitude still matches that of coal IOR, and thus, only minor differences in the radiative properties of coal and biomass are expected.
{"title":"Experimental determination of the optical properties of walnut shell particles","authors":"Matthias Koch , Stefan Pielsticker , Jochen Ströhle , Reinhold Kneer","doi":"10.1016/j.jqsrt.2024.109202","DOIUrl":"10.1016/j.jqsrt.2024.109202","url":null,"abstract":"<div><div>The index of refraction (IOR) is required to model thermal radiation interaction with pulverized solid fuels. In this work, the complex index of refraction of biomass (walnut shell) is therefore determined using pulverized particles. Single particles are irradiated, and the scattered radiation is measured in different directions. To avoid falsification of the scattering pattern (phase function), the particles are kept contactless in an acoustic levitator. Here, over 1000 different phase functions are measured. The measured scattering patterns are evaluated using an inverse evaluation procedure to determine the IOR. Mie theory serves as the basis for the mathematical modeling of the radiation properties of the particles. The measured IOR is then compared to data from the literature on coal. For the wavelength range <span><math><mrow><mi>λ</mi><mo>=</mo><mn>2000</mn><mtext>–</mtext><mn>4000</mn><mspace></mspace><mi>nm</mi></mrow></math></span> no distinct differences are noticed between the coal and biomass IOR. For <span><math><mrow><mi>λ</mi><mo>></mo><mtext>4000</mtext><mspace></mspace><mtext>nm</mtext></mrow></math></span> the real part of the biomass IOR is larger and the differences increase with increasing wavelength. However, the order of magnitude still matches that of coal IOR, and thus, only minor differences in the radiative properties of coal and biomass are expected.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109202"},"PeriodicalIF":2.3,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423787","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 : 2024-09-30DOI: 10.1016/j.jqsrt.2024.109201
Huan Tang , Zhuoyuan Shi , Yuan Zhang , Renxian Li , Bing Wei , Shuhong Gong , Igor V. Minin , Oleg V. Minin
The exact expression of the wave vector inside a spinning homogeneous dielectric sphere illuminated by polarized plane waves is derived utilizing the “instantaneous rest-frame” hypothesis and Minkowski’s theory. On this basis, the analytical expressions of the electromagnetic field in the rotation sphere system are attained. The asymmetry of the system is discussed, in which the cause is emphasized. The influence of the polarization states and rotation angular velocity on the scattering are analyzed, including the optical rotation effect and photonic hook (PH). The results of this manuscript have extensive application prospects in optical tweezers, particle manipulation, and antenna design.
{"title":"Scattering of a spinning dielectric sphere to polarized plane waves","authors":"Huan Tang , Zhuoyuan Shi , Yuan Zhang , Renxian Li , Bing Wei , Shuhong Gong , Igor V. Minin , Oleg V. Minin","doi":"10.1016/j.jqsrt.2024.109201","DOIUrl":"10.1016/j.jqsrt.2024.109201","url":null,"abstract":"<div><div>The exact expression of the wave vector inside a spinning homogeneous dielectric sphere illuminated by polarized plane waves is derived utilizing the “instantaneous rest-frame” hypothesis and Minkowski’s theory. On this basis, the analytical expressions of the electromagnetic field in the rotation sphere system are attained. The asymmetry of the system is discussed, in which the cause is emphasized. The influence of the polarization states and rotation angular velocity on the scattering are analyzed, including the optical rotation effect and photonic hook (PH). The results of this manuscript have extensive application prospects in optical tweezers, particle manipulation, and antenna design.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109201"},"PeriodicalIF":2.3,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423823","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 : 2024-09-30DOI: 10.1016/j.jqsrt.2024.109205
O.N. Ulenikov , O.V. Gromova , E.S. Bekhtereva , Yu.S. Aslapovskaya , Yu.V. Sypchenko , C. Sydow , C. Maul , S. Bauerecker
<div><div>A highly accurate rotational–vibrational analysis of Fourier transform infrared spectra of the <span><math><msup><mrow></mrow><mrow><mn>12</mn></mrow></msup></math></span>CD<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> molecule is presented. The high resolution infrared spectra were measured with a IFS125 HR Fourier transform interferometer from Bruker at an optical resolution of 0.003 cm<sup>−1</sup> and analyzed in the 1750–2400 cm<sup>−1</sup> region. Here the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <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> bands (altogether, nine sub-bands of different symmetry) of the pentad are located. The number of 1213/1993/1576/77/1582 transitions with the <span><math><msup><mrow><mi>J</mi></mrow><mrow><mtext>max</mtext></mrow></msup></math></span> = 23/23/23/14/32 were assigned to the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <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> bands of <span><math><msup><mrow></mrow><mrow><mn>12</mn></mrow></msup></math></span>CD<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span>. The obtained experimental data were used for the determination of the upper ro-vibrational energy values. To provide more correct values of the upper energies, more than 7800 highly accurate “hot” transitions from the dyad region were additionally processed. In general, 4088 upper ro-vibrational energies of the pentad (for comparison, 2525 upper ro-vibrational energies with the value of <span><math><mrow><msup><mrow><mi>J</mi></mrow><mrow><mtext>max</mtext></mrow></msup><mo>=</mo><mn>20</mn></mrow></math></span> are known in the modern literature up to now) were determined, which were used then in the weighted fit procedure with a goal to determine the spectroscopic parameters (band centers, rotational, centrifugal distortion, tetrahedral splitting and resonance interaction parameters) of the effective Hamiltonian. The obtained <span><math><msub><mrow><mi>d</mi></mrow><mrow><mtext>rms</mtext></mrow></msub></mat
{"title":"High resolution analysis of the CD4 deuterated methane: Extended investigation of the pentad region","authors":"O.N. Ulenikov , O.V. Gromova , E.S. Bekhtereva , Yu.S. Aslapovskaya , Yu.V. Sypchenko , C. Sydow , C. Maul , S. Bauerecker","doi":"10.1016/j.jqsrt.2024.109205","DOIUrl":"10.1016/j.jqsrt.2024.109205","url":null,"abstract":"<div><div>A highly accurate rotational–vibrational analysis of Fourier transform infrared spectra of the <span><math><msup><mrow></mrow><mrow><mn>12</mn></mrow></msup></math></span>CD<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> molecule is presented. The high resolution infrared spectra were measured with a IFS125 HR Fourier transform interferometer from Bruker at an optical resolution of 0.003 cm<sup>−1</sup> and analyzed in the 1750–2400 cm<sup>−1</sup> region. Here the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <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> bands (altogether, nine sub-bands of different symmetry) of the pentad are located. The number of 1213/1993/1576/77/1582 transitions with the <span><math><msup><mrow><mi>J</mi></mrow><mrow><mtext>max</mtext></mrow></msup></math></span> = 23/23/23/14/32 were assigned to the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>, <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> bands of <span><math><msup><mrow></mrow><mrow><mn>12</mn></mrow></msup></math></span>CD<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span>. The obtained experimental data were used for the determination of the upper ro-vibrational energy values. To provide more correct values of the upper energies, more than 7800 highly accurate “hot” transitions from the dyad region were additionally processed. In general, 4088 upper ro-vibrational energies of the pentad (for comparison, 2525 upper ro-vibrational energies with the value of <span><math><mrow><msup><mrow><mi>J</mi></mrow><mrow><mtext>max</mtext></mrow></msup><mo>=</mo><mn>20</mn></mrow></math></span> are known in the modern literature up to now) were determined, which were used then in the weighted fit procedure with a goal to determine the spectroscopic parameters (band centers, rotational, centrifugal distortion, tetrahedral splitting and resonance interaction parameters) of the effective Hamiltonian. The obtained <span><math><msub><mrow><mi>d</mi></mrow><mrow><mtext>rms</mtext></mrow></msub></mat","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109205"},"PeriodicalIF":2.3,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423786","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 : 2024-09-29DOI: 10.1016/j.jqsrt.2024.109204
Prakash Gautam , Hans Moosmüller , Justin B. Maughan , Christopher M. Sorensen
The purpose of this paper is to study the dependency of light backscattering on particle physical properties: size, refractive index, and shape; and to demonstrate the extreme sensitivity of backscattering on these properties. We demonstrate how the nondescript backscattering pattern evolves seemingly chaotic, in contrast to the orderly forward scattering, with the particle's physical properties. The demonstration was carried out by light scattering from water droplets and with spherical particle Mie theory. Our results show systematic, descriptive evolution of the forward scattering pattern, which is clearly shown in logarithmic Q–space, whereas non-descriptive, chaotic evolution within the backscattering regime is displayed in linear θ–space. Additionally, our study shows that within the last 1°, the backscattering intensity remains constant and featureless for the ∼ 2.5 μm diameter water droplets investigated here.
{"title":"Sensitivity of backscattering to spherical particle physical properties: Size, refractive index, and shape deviations","authors":"Prakash Gautam , Hans Moosmüller , Justin B. Maughan , Christopher M. Sorensen","doi":"10.1016/j.jqsrt.2024.109204","DOIUrl":"10.1016/j.jqsrt.2024.109204","url":null,"abstract":"<div><div>The purpose of this paper is to study the dependency of light backscattering on particle physical properties: size, refractive index, and shape; and to demonstrate the extreme sensitivity of backscattering on these properties. We demonstrate how the nondescript backscattering pattern evolves seemingly chaotic, in contrast to the orderly forward scattering, with the particle's physical properties. The demonstration was carried out by light scattering from water droplets and with spherical particle Mie theory. Our results show systematic, descriptive evolution of the forward scattering pattern, which is clearly shown in logarithmic Q–space, whereas non-descriptive, chaotic evolution within the backscattering regime is displayed in linear θ–space. Additionally, our study shows that within the last 1°, the backscattering intensity remains constant and featureless for the ∼ 2.5 μm diameter water droplets investigated here.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109204"},"PeriodicalIF":2.3,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423840","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 : 2024-09-29DOI: 10.1016/j.jqsrt.2024.109209
Ahmed El-Habashi , Samir Ahmed
The impact of the un-polarized nature of chlorophyll fluorescence, which causes a dip in the degree of polarization of the underwater light field matching the fluorescence spectrum, led to the development of a theoretical relationship indicating that the resulting fractional reduction in observed polarization is linearly proportional to the magnitude of the fluorescence causing it. To evaluate this relationship, we used a vector radiative transfer code (VRTE) for the coupled atmosphere-ocean system using measured inherent optical properties (IOPs) for a variety of oligotrophic and eutrophic waters as inputs. The VRTE was used to simulate elastic components of the underwater reflectance as well as the degree of linear polarization (DoLP) for these different conditions. These values were compared with the underwater reflectances and the DoLPs measured by a multi-angular hyperspectral polarimeter to determine the magnitude of the fluorescence component in the reflectance spectra at 685 nm, and the decrease of the DoLP due to the fluorescence impact at the same wavelength. Fluorescence magnitudes retrieved from the differences between simulated and measured reflectances were found to match well the magnitudes estimated through the relationship based on the drop of the DoLP. It is noted that retrieval accuracies increase for both larger fluorescence and larger underlying DoLP values. Furthermore, a new method is evolved from the measured polarization analysis, Polarization-Curve Fluorescence Height (PCFH). Measured polarization were used to approximate the elastic signal and derive the inelastic un-polarized signal (fluorescence) from the difference in the fluorescence vicinity. These results open possibilities for estimating the magnitude of natural fluorescence using polarization measurements below or above the water surface, .in-situ, or remotely from aircraft or future satellites. Results of ongoing work on potential sensitivities and retrieval accuracies for these applications will be reported.
{"title":"The relationship between chlorophyll fluorescence and polarized light field: Polarization-curve fluorescence height","authors":"Ahmed El-Habashi , Samir Ahmed","doi":"10.1016/j.jqsrt.2024.109209","DOIUrl":"10.1016/j.jqsrt.2024.109209","url":null,"abstract":"<div><div>The impact of the un-polarized nature of chlorophyll fluorescence, which causes a dip in the degree of polarization of the underwater light field matching the fluorescence spectrum, led to the development of a theoretical relationship indicating that the resulting fractional reduction in observed polarization is linearly proportional to the magnitude of the fluorescence causing it. To evaluate this relationship, we used a vector radiative transfer code (VRTE) for the coupled atmosphere-ocean system using measured inherent optical properties (IOPs) for a variety of oligotrophic and eutrophic waters as inputs. The VRTE was used to simulate elastic components of the underwater reflectance as well as the degree of linear polarization (DoLP) for these different conditions. These values were compared with the underwater reflectances and the DoLPs measured by a multi-angular hyperspectral polarimeter to determine the magnitude of the fluorescence component in the reflectance spectra at 685 nm, and the decrease of the DoLP due to the fluorescence impact at the same wavelength. Fluorescence magnitudes retrieved from the differences between simulated and measured reflectances were found to match well the magnitudes estimated through the relationship based on the drop of the DoLP. It is noted that retrieval accuracies increase for both larger fluorescence and larger underlying DoLP values. Furthermore, a new method is evolved from the measured polarization analysis, Polarization-Curve Fluorescence Height (PCFH). Measured polarization were used to approximate the elastic signal and derive the inelastic un-polarized signal (fluorescence) from the difference in the fluorescence vicinity. These results open possibilities for estimating the magnitude of natural fluorescence using polarization measurements below or above the water surface, <em>.in-situ</em>, or remotely from aircraft or future satellites. Results of ongoing work on potential sensitivities and retrieval accuracies for these applications will be reported.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109209"},"PeriodicalIF":2.3,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423839","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}
The cavity ring-down spectra (CRDS) of nitrous oxide were recorded at a pressure of 10 hPa in the 11,937–12,223 cm-1 range with a threshold sensitivity to absorption coefficient of the order of 6.5 × 10–11 cm-1. Three bands (ν1+5ν3, 6ν1+2ν3, and 3ν1+4ν3) were detected. The line centers and intensities were recovered from the observed spectra. The spectroscopic constants of the upper vibrational states and the vibrational transition dipole moment parameters were fitted to the measured line positions and intensities, respectively. It was found that the 3ν1+4ν3 band is in the interpolyad Coriolis resonance interaction with the band. This interaction leads to the appearance in the spectra of the four extra lines of the band.
{"title":"Cavity ring-down spectroscopy of 14N216O near 0.83 µm","authors":"L.N. Sinitsa, S.S. Vasilchenko, N.M. Emelyanov, A.A. Marinina, V.I. Perevalov","doi":"10.1016/j.jqsrt.2024.109210","DOIUrl":"10.1016/j.jqsrt.2024.109210","url":null,"abstract":"<div><div>The cavity ring-down spectra (CRDS) of nitrous oxide were recorded at a pressure of 10 hPa in the 11,937–12,223 cm<sup>-1</sup> range with a threshold sensitivity to absorption coefficient of the order of 6.5 × 10<sup>–11</sup> cm<sup>-1</sup>. Three bands (<em>ν</em><sub>1</sub>+5<em>ν</em><sub>3</sub>, 6<em>ν</em><sub>1</sub>+2<em>ν</em><sub>3</sub>, and 3<em>ν</em><sub>1</sub>+4<em>ν</em><sub>3</sub>) were detected. The line centers and intensities were recovered from the observed spectra. The spectroscopic constants of the upper vibrational states and the vibrational transition dipole moment parameters were fitted to the measured line positions and intensities, respectively. It was found that the 3<em>ν</em><sub>1</sub>+4<em>ν</em><sub>3</sub> band is in the interpolyad Coriolis resonance interaction with the <span><math><mrow><mn>7</mn><msub><mi>ν</mi><mn>1</mn></msub><mo>+</mo><mn>7</mn><msubsup><mi>ν</mi><mn>2</mn><mn>1</mn></msubsup></mrow></math></span> band. This interaction leads to the appearance in the spectra of the four extra lines of the <span><math><mrow><mn>7</mn><msub><mi>ν</mi><mn>1</mn></msub><mo>+</mo><mn>7</mn><msubsup><mi>ν</mi><mn>2</mn><mn>1</mn></msubsup></mrow></math></span> band.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"329 ","pages":"Article 109210"},"PeriodicalIF":2.3,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423849","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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