We report on our theoretical analysis of the hyperfine splitting in the spectra of the 13Δg, 23Πg, and 33Σg+ triplet states of 6Li7Li, which were experimentally observed in 2002 (Li et al.) by means of Perturbation Facilitated Optical-Optical Double Resonance (PFOODR) spectroscopy. In our previous work, both homonuclear and heteronuclear molecules were analyzed. However, in this work, we theoretically

Radium compounds have attracted recently considerable attention due to both development of experimental techniques for high-precision laser spectroscopy of molecules with short-lived nuclei and amenability of certain radium compounds for direct cooling with lasers. Currently, radium monofluoride (RaF) is one of the most studied molecules among the radium compounds, both theoretically and recently also

Atomic properties of n=3 states of the W56+ - W61+ ions are systematically investigated through two state-of-the-art methods, namely, the second-order many-body perturbation theory, and the multi-configuration Dirac–Hartree–Fock method combined with the relativistic configuration interaction approach. The contributions of valence-valence and core-valence electron correlations, the Breit interaction

Large amounts of fine polluted particles due to anthropogenic activities can enter into the lower atmosphere and may pollute the lower water clouds, especially continental cumulus. Continental polluted cumulus (CPCU) plays an important role in the process of atmospheric radiative transfer and the Earth's environmental change. Based on the sensitivity of polarization to small particles, GF-5 DPC data

A synthetic line list for the ozone molecule is presented. Variational calculation using the semi-empirical potential energy surface (PES) and ab initio dipole moment surface (DMS) produce very accurate values of line intensities, but give line positions far away from their experimental values. Furthermore assignment of approximate rotational and vibrational quantum numbers are missing from variationally

A hydrogen cyanide line list (MOMeNT-90) developed for the HITRAN spectroscopic database covering 07500 cm−1 range (λ>1330 nm) is presented. The line list is a combination of the variationally calculated line intensities with line centers obtained from experimentally derived energy levels. There are four features of this line list which distinguishes it from the previously calculated ones. First, the

We measured air broadening in the (30012) ← (00001) carbon dioxide (CO2) band up to Jʺ = 50 using frequency-agile rapid scanning cavity ring-down spectroscopy. By using synthetic air samples with varying levels of nitrogen, oxygen, and argon, multi-spectrum fitting allowed for the collisional broadening terms of each major air component to be simultaneously determined in addition to advanced line shape

We report energy level structure of triply ionized mercury (Hg IV). The spectrum was recorded on a 3-m normal incidence vacuum spectrograph in the wavelength region 300 – 2000 Å, using a triggered spark source at the spectroscopy laboratory, St. Francis Xavier University, Antigonish in Canada. Wavelength measurement and the corresponding uncertainties caused by calibration procedures are carefully

The thallium hydride (TIH) is one of the most promising standard test molecular systems containing heavy-elements of relativistic quantum mechanical techniques. Here, we have investigated the low-lying electronic states in TlH using the multireference configuration interaction method including the core-valence correlations and spin-orbit coupling effects. The ground and excited electronic states of

We report a list of positions and intensities of 331 892 hyperfine components of all 18 585 rovibrational dipole transitions in the HT and DT isotopologues of molecular hydrogen. Apart from the study of hyperfine structure, we investigate the intensities of all rovibrational dipole transitions in the two isotopologues, which were not known prior to this work. The results presented here are crucial

A significant challenge for plasmonics as an enabling technology for energy harvesting and conversion processing is the active control of light on the nanoscale. By exploiting the resonant absorption spectra of silver nanoparticle dimer array, the theoretical results show that the resonant transverse mode and longitudinal mode is defined by the direction of dipole moment. Both of this two kind of plasmonic

In chirped pulse experiments, magnitude Fourier transform is used to generate frequency domain spectra. The application of window function as a tool for lineshape correction and signal-to-noise ratio (SnR) enhancement is rarely discussed in chirped spectroscopy, with the only exception of using Kaiser-Bessel window and trivial rectangular window. We present a specific window function, called “Voigt-1D”

Optothermal traps including vortex ones, have been implemented to capture and manipulate transparent and absorbing micro-objects. The current study deals with latex microspheres of various diameters and silver microparticles. The temperature gradient and corresponding convection fluxes of the liquid were formed by using a light filter absorbing at a wavelength of 0.53 μm as the bottom of the cell with

The Kr M4,5-NN Auger transitions are studied in the kinetic energy region 24 - 59 eV by using non-monochromatic electron beam and a high resolution electrostatic analyzer. Among the sixty four features observed, fifty five are assigned, while nine stay unassigned. The post-collision interaction (PCI) effects in the M5-N1N1(1S0) and M5-N2,3N2,3(1S0) Auger peaks are studied as a function of electron

In this paper the Mueller polarimetry is applied to study the four natural samples in visible (λ = 632.8 nm): soil, sand, clay and moss. To quantify separability of these samples based on their Mueller matrices we analyze their experimental Mueller matrices by calculating a number of single value depolarization metrics (degree of polarization, average degree of polarization, depolarization index, Q(M)-metric)

In this paper Mueller polarimetry is applied to study some natural scatter scenes in visible: soil, sand, clay and moss. To obtain the anisotropic and depolarizing properties of the samples under study, the existing additive and multiplicative decompositions of experimental Mueller matrices were used. It is shown that all samples are characterized by anisotropic depolarization: the highest depolarization

The scattering of a non-paraxial Bessel pincer light-sheet by a dielectric sphere of arbitrary size is studied in the framework of generalized Lorenz-Mie theory (GLMT). The electrical field of the Bessel pincer light-sheet is expanded using the vector angular spectrum decomposition method (VASDM), and its beam shape coefficients (BSCs) are derived using the method of multipole expansion and vector

In this article, we present a T-matrix method for numerical computation of second-harmonic generation from clusters of arbitrarily distributed spherical particles made of centrosymmetric optical materials. The electromagnetic fields at the fundamental and second-harmonic (SH) frequencies are expanded in series of vector spherical wave functions, and the single sphere T-matrix entries are computed by

The machine learning based full-spectrum correlated k-distribution (FSCK) model previously developed by Zhou et al. (2020), provides a compact prediction model with good efficiency and accuracy for the evaluation of radiative spectral calculations in nonhomogeneous gaseous media. However, the model is only for gas mixtures of CO2, CO, H2O, and cannot be used for gas-soot mixtures that are found in

Accurate absorption models for gases at high pressure and temperature support advanced optical combustion diagnostics and aid in the study of harsh planetary atmospheres. Developing and validating absorption models for these applications requires recreating the extreme temperature and pressure conditions of these environments in static, uniform, well-known conditions in the laboratory. Here, we present

The spectroscopy of the υ = 1 → υ = 0 fundamental vibration-rotation band of nitric oxide (NO) in Earth's atmosphere is examined in depth in order to further assess the long-running dataset of infrared radiative cooling rates in the thermosphere from the SABER instrument on the NASA TIMED satellite. The fundamental band at 5.3 µm is shown to be almost solely responsible for the cooling by NO. The distribution

The high variability of atmospheric aerosol in space and time poses significant challenges for aerosol observation and simulation, as well as for the design of aerosol monitoring systems. Multi-Angular Polarimeters (MAP) have been identified to provide highly accurate data for characterizing in detail columnar properties of atmospheric aerosol. Obtaining such multi-angular observations at high spatial

Characterization of particle size and shape is important in studying particle field changes. Interferometric particle imaging is a reliable technique that is widely used in the characterization of droplets or bubbles. In recent years, this method has also been used to measure irregular rough particles. According to the distribution of emitting points, the projected 2D shape of particles can be obtained

The core-shell nanoparticles are greatly advocated for their usefulness in biomedical applications tending to targeted drug delivery, sensing, and bio-imaging. In this paper, the optical properties of simple; Ni@Ag/Au and complex; NiFe@Ag/Au magnetoplasmonic nanoparticles for their core-shell structures with spherical and prolate geometries are comprehensively investigated using the discrete dipole

The paper presents analytical expressions for the dielectric function, refractive index, absorption coefficient and reflection coefficient of radiation in a classical two-component fully ionized plasma. The expressions are based on the results of numerical calculations of the conductivity for the ultracold plasma model. These analytical expressions have simple form and depend only on two dimensionless

This study presents an approximative approach to solve the radiative transfer equation accounting for the rotational Raman scattering in a spherical atmosphere. The solution is obtained employing the method of characteristics in combination with the discrete-ordinates technique and the forward-adjoint perturbation theory. For a non-limb observational geometry, impact of the atmospheric sphericity on

This work theoretically studies a spectrally selective nanophotonic cell based on an asymmetric Fabry-Perot resonance cavity structure with sub-100-nm GaSb layer for improving the thermophotovoltaic (TPV) energy conversion performance. The simulated spectral property of the ultrathin metafilm cell structure exhibits a high absorption peak above the bandgap due to the interference effect with electromagnetic

From November 2019 to June 2020, horizontally oriented ice crystal (HOIC) layers were observed on 32 occasions using the synergy of zenith- and slant-pointed polarization lidar over Wuhan (30.5°N, 114.4°E), China. The HOIC layers appeared at altitudes of 2.5–10.5 km. 20 out of 32 cases showed a specific period that HOIC layers maintained in the atmosphere without an evident sign of orientation breakup

Theoretically, laser beam divergence can redistribute multiple scattering lights by spreading laser illumination and thus alter lidar polarization measurements. To study multiple scattering effects of laser divergence on lidar polarization signals, we apply the Monte Carlo polarized radiative transfer model MSCART to simulate lidar Stokes vector signals from a uniform water cloud with and without taking

The spectrum of Praseodymium was investigated in the visible region from 4000 Å to 7500 Å based on previously recorded Fourier Transform spectra. Source of free Pr atoms was a hollow cathode discharge lamp. The investigation of spectral lines was performed using laser-induced fluorescence spectroscopy. A tunable single mode ring-dye laser, pumped by a frequency doubled Nd-YAG laser, was used as the

Wide wavelength range with high-resolution emission spectroscopy was applied to LHD peripheral plasmas. All measured Fulcher-a band Q-branches spectra (600–630 nm) were measured with a single shot exposure time of 100–200 ms for all investigated discharges. Ro-vibrational populations up to v = 2 and N = 11 for H2 and up to v = 3 and N = 14 for D2 in the 3p3Πu state were estimated, where v and N are

The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) acquires radiance measurements in eight spectral bands centered at 355, 380, 445, 470*, 555, 660*, 865*, and 935 nm, three of which also measure linear polarization (denoted by asterisks). A two-step retrieval approach is developed to retrieve total precipitable water vapor (PWV) abundance: a) the first step is a fast estimate of water vapor

The sky in the Malvern Hills Area of Outstanding Natural Beauty (MHAONB) has been monitored continually since 2012, when a dark sky survey of the area was carried out commissioned by Malvern Hills Conservators. Ever since then at F.C. Observatory Mathon, the sky brightness has been measured continually, in the last few years at minute intervals in all weathers. On the darkest of nights, a fisheye lensed

Difluoromethane (CH2F2; HFC-32), a hydrofluorocarbon (HFC) used as a refrigerant in air conditioning and heat pump systems, is currently being phased out under the terms of the Montreal Protocol (Kigali Amendment). In order to monitor its concentration profiles using infrared-sounding instruments, for example the Atmospheric Chemistry Experiment – Fourier transform spectrometer (ACE-FTS), accurate

We describe a technique for preparing highly charged Au nanospheres that can be collected in a quadrupole ion trap and heated beyond the melting point of Au, using a laser, without discharging. Au nanospheres are first added to solutions of (NH4)2CO3to prepare stable suspensions. Electrospray emission of these suspensions introduces single Au nanospheres into an ion trap in high vacuum, where their

Spectra of pure isobutane were recorded at high temperature in the C-H stretching region (2750-3050 cm−1) with a high resolution Fourier transform spectrometer. Isobutane absorption cross sections were determined for six temperatures from 295 K to 739 K. These data may be useful for simulations of hot Jupiter exoplanets and brown dwarfs. Integrated cross sections were compared with adjusted cross section

We discuss the current state of the Ukrainian space project Aerosol-UA, which aims to provide data on the aerosol spatial distribution and microphysics in the Earth's atmosphere. The Aerosol-UA remote sensing concept is based on measurements from the multispectral Scanning Polarimeter (ScanPol) and the MultiSpectral Imaging Polarimeter (MSIP) on board the Yuzhnoe satellite (YuzhSat) platform. The ScanPol

In this paper, we used requantized Classical Molecular Dynamics Simulations (rCMDS), corrected by the room temperature air-broadening coefficients measured in the ν3 band of N2O, to predict line-shape parameters including the broadening coefficient, its speed dependence component, the Dicke narrowing and the line-mixing coefficients, associated with various line-shape models for air-broadened N2O absorption

We present a spectral model for optical non-invasive estimation of layer thickness and water/ice content on diffusely reflecting substrate materials based on a single near-infrared spectrum. Using the wavelength range from 850 nm to 1650 nm which is readily accessible with InGaAs detectors, a wide range of layer thicknesses from tens of micrometers to several centimeters can be determined. The model

In this paper, the depolarization effect of the two-orthogonal polarized microwaves (MWs) by spheroid sand-dust particles in atmospheric turbulence is studied based on T-matrix theory. The results indicate that the depolarization effect by spheroidal particles can be weakened in turbulence, namely, as the turbulent intensity increases, the cross-polarization discrimination (XPD) of the MWs increases

Optical forces on electric dipoles are usually expressed in terms of the incident electric field components. Gradient forces are then expressed in terms of the electric intensity gradient, while standard and nonstandard scattering forces are found to be physically coupled to contributions associated with both the Poynting vector and an additional term attached to the spin angular momentum of the incident

We demonstrate a method of classifying aerosol particles with different shapes based on the two separated vertical and horizontal polarized beams spaced by 90-100 µm. Model 3321 Aerodynamic Particle Sizer Spectrometer (APS3321) was used to set up an experimental apparatus to test aerosol samples of different shapes, such as spherical oleic acid droplets and elongated crystallized riboflavin. The receiver

A comprehensive computational study on the electronic states of SnH correlated with lowest 5 atomic limits is carried out using internally contracted multireference configuration interaction method (icMRCI) in combination with all-electron correlation-consistent basis set. The Davidson correction (+Q) and spin-orbit coupling (SOC) are taken into account in the calculations of the potential energy curves

Atmospheric ice crystals scatter sunlight, affecting Earth’s climate through the radiation properties of cirrus clouds. Naturally occuring surface roughness and its effect on the scattering properties of ice crystals remain largely unknown. Scattering by ice crystals with rough surfaces is studied by placing a finite, thin surface-roughness element on an infinitely large, planar vacuum-ice boundary

We used some archival data from the Fourier transform spectrometer (FTS) at the US National Solar Observatory to study the hyperfine structure (HFS) patterns of Co I and Co II, and determined the HFS constants of Co I and Co II. In total, HFS constants A for 36 levels of Co I from 0.00 to 60,262.463 cm−1 and for 61 levels of Co II from 11,651.277 to 85,876.271 cm−1 were determined, of which 33 results

The problem of light scattering and absorption is considered for a free-standing two-dimensional array (monolayer) of nano- and micrometer spherical silver particles. To solve this problem for short- and imperfect long-range ordered arrays the statistical theory of multiple scattering of waves is used. The key points of the developed semi-analytical method are described. The method is based on the

Efficient absorption of solar spectral radiation is a key requirement in solar heat utilization. In an effort to achieve this goal, this study investigated slow light effect and magnetic polaritons, and analyzed other physical model coupling mechanisms in photonic crystals. To construct a class of two-dimensional layers of Ni-Al2O3 as a pyramid array solar energy absorber, the high melting points of

The Rayleigh limit of the generalized Lorenz-Mie theory (GLMT) has been recently examined in the case of off-axis circularly symmetric Bessel beams, thereafter in the case of on-axis circularly symmetric Bessel beams, the on-axis case providing an easier framework for the understanding of the optical forces exerted in the Rayleigh limit of GLMT. This work is here extended to the case of non dark on-axis

We develop a dipole model describing the thermal far-field radiation of a nanoparticle in close vicinity to a substrate. By including in our description the contribution of eddy currents and the possibility to choose different temperatures for the nanoparticle, the substrate, and the background, we generalize the existing models. We discuss the impact of the different temperatures, particle size, emission

A semi-classical and a semi-empirical methods are employed to obtain line-broadening coefficients for the ν6 band of CH3I-N2 at room temperature (296 K). Calculations are performed for lines in the R, P and Q branches in a broad range of rotational quantum numbers (0≤J≤70, K≤20) typically required for spectroscopic databases. The results demonstrate a good consistency with available Voigt-profile measurements

In this paper, we explore the far-field radiative thermal rectification potential of common materials such as metals,ceramics and doped semi-conductors using radiative and thermo-radiative properties extracted from literature. Seventeen different materials are considered. The rectification coefficient is then calculated for 136 pairs of materials; each pair can be used for the two terminals of a radiative

In the weak-magnetic-field approximation, we calculated the hyperfine-induced Landé g-factors of the 3P0o clock states in 27Al+ and 87Sr by using the multi-configuration Dirac–Hartree–Fock method. The present results, δghfs(1)(3P0o)=−1.183(6)×10−3 for 27Al+ and δghfs(1)(3P0o)=7.78(30)×10−5 for 87Sr, agree with experimental values very well. The influence of relativistic effects and electron correlations

Atomic spectral data of six argon ions from Ar9+ to Ar14+ are calculated by combining the relativistic multi-configuration interaction method and the many-body perturbation theory (FAC-MBPT) method. Transitions from shell number n=2 to shell numbers n=3, 4, 5, and 6 are investigated where relativistic effects, correlation effects, and QED effects are applied. Experimental transition lines often demonstrate