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In this paper we present a new result involving the properties of the Clebsch–Gordan coefficients well-used in atomic physics. We also demonstrate a practical use of this result: a new and simple method of calculation of unit tensor operators of multi-electron atoms while working within the Slater–Condon scheme. This results in a significant increase in the ease of implementation of multi-electron...
The relative intensities of nine emission bands associated with the v′=0 and 1 vibrational levels of the B2Σ+–X2Σ+ system of the BO molecule are measured. The integrated relative intensities of the (0, 0), (0, 1), (1, 0) and (1, 1) bands are measured for the first time in this work. The ratios of observed intensities for bands originating from the same upper vibrational level, together with the Franck–Condon...
A simple model of the water dimer millimeter-wave spectrum at pressures and temperatures typical of Earth׳s atmosphere is proposed. The model is based on high accuracy ab initio calculations and is supported by experimental observations of the dimer spectrum in cold molecular beams. It is demonstrated that the model corresponds to the spectra calculated ab initio and recorded at room temperature....
An empirical line list has been constructed for “natural” water vapor at 296K in the 5850–7920cm −1 region. It was obtained by gathering separate line lists recently published on the basis of spectra recorded by high sensitivity Continuous Wave Cavity Ring Down Spectroscopy (CW-CRDS) of natural water, complemented with literature data for the strongest lines. The list includes 38,318 transitions...
The concept of differential absorption has been widely used in UV and shortwave remote sensing. This study explores how to extend such concept to the thermal-IR for fast estimation of the total column water vapor (CWV) from clear-sky IR radiances. Using Atmospheric Infrared Sounder (AIRS) radiances as a case study, double difference of radiances at two pairs of pre-selected AIRS channels can be used...
This paper reports ytterbium-doped lead phosphate (PbPhYb) glasses made by melt-quenching technique and their linear and nonlinear refractive indices. Raman and FTIR spectral analysis has been carried out to investigate the functional groups that constitute the host matrix. The oscillator strength of the absorption transition, ( 2 F 7/2 → 2 F 5/2 ) has been evaluated...
We present a line-shape study of six absorption lines P(21), P(16), P(19), R(16), R(19) and R(21) in the ν 1 +ν 3 band of the acetylene perturbed by nitrogen. The spectra were recorded using a 3-channel diode laser spectrometer. For each transition studied, the N 2 -broadening, N 2 -narrowing, N 2 -pressure induced line shift and N 2 -line mixing coefficients...
The pressure broadening and shift rates for the K D 2 (4P3/22←4S1/22) transition with N 2 , CH 4 , C 2 H 6 , C 3 H 8 , n-C 4 H 10 , and the noble gases were obtained for pressures up to 80 Torr and at a temperature of 55°C by means of laser absorption spectroscopy. Additionally, the broadening and shift rates for the Rb D ...
This paper analyses high spectral resolution downwelling radiance measurements in the far infrared in the presence of cirrus clouds taken by the REFIR-PAD interferometer, deployed at 3500m above the sea level at the Testa Grigia station (Italy), during the Earth COoling by WAter vapouR emission (ECOWAR) campaign. Atmospheric state and cloud geometry are characterised by the co-located millimeter-wave...
Fractal-like aggregates are commonly modeled as assemblies of spheres positioned in point contact only. The necking phenomenon is usually neglected. Such an approach has some advantages, e.g. faster light scattering simulation programs can be used, however, it may result in many additional errors and inaccuracies. In our study we try to approximate them and select the most suitable connection model...
Yb/Bi co-doped borophosphate glasses and fibers were prepared. The effect of Yb 3+ on the near-infrared (NIR) luminescent properties and the mechanism of luminescence of Bi-ions were investigated. Under 976nm laser diode (LD) excitation, the NIR emission intensity of the glass with 8mol% Yb 2 O 3 co-doped glass is ~37 times stronger than that of Bi singly-doped glass. The fluorescence...
A new implementation to determine the correlated k values as used in full-spectrum correlated k-distribution methods for inhomogeneous media is presented, which conserves radiative emission and significantly improves the accuracy of the full-spectrum correlated k-distribution method in strongly inhomogeneous media. In addition, an update of a previous high-accuracy, compact narrow-band k-distribution...
The study of temperature dependence of thermophysical parameter dielectric function is key to understanding thermal radiative transfer in high-temperature environments. Limited by self-radiation and thermal oxidation, however, it is difficult to directly measure the high-temperature dielectric function of solids with present experimental technologies. In this work, we implement two first-principles...
Atmospheric temperature profiles are inferred from passive satellite instruments, using thermal infrared or microwave observations. Here we investigate on the feasibility of the retrieval of height resolved temperature information in the ultraviolet spectral region. The temperature dependence of the absorption cross sections of ozone in the Huggins band, in particular in the interval 320–325nm, is...
In the first part of this paper the general theory of relaxation parameters of the spectrum shape in the impact approximation was presented. Here we describe some simplifications, discuss the isolated line approximation and compare our results with the other methods of a spectral line half-width and center shift calculation. As an example, illustrative calculations of the q Q(J,K) doublets...
Electron-impact excitation and resonant electron capture cross sections to the specific magnetic sublevels as well as the polarization of the strong nf→3d (n=4, 5, 6) x-ray emitted from Ni-like through Ge-like tungsten ions have been studied systematically by using a fully relativistic distorted-wave method. We compare the polarizations for the same x-ray but from the above two different processes...
Porous material has been considered from the point of view of stereology (geometrical statistics), as a two-phase random mixture of solid material and air. Considered are the materials having the refractive index with the real part that differs notably from unit and the imaginary part much less than unit. Light scattering in such materials has been described using geometrical optics. These two – the...
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