He-broadening and shift coefficients of water vapor lines in infrared spectral region

The water vapor line broadening and shift coefficients in the ν1+ν2, ν2+ν3, ν1+ν3, 2ν3, 2ν1, 2ν2+ν3, and ν1+2ν2 vibrational bands induced by helium pressure were measured using a Bruker IFS 125HR spectrometer. The vibrational bands 2ν3 and ν1+2ν2 were investigated for the first time. The interaction potential used in the calculations of broadening and shift coefficients was chosen as the sum of pair potentials, which were modeled by the Lennard-Jones (6-12) potentials. The vibrational and rotational contributions to this potential were obtained by use of the intermolecular potential parameters and intramolecular parameters of H2O molecule. The calculated values of the broadening and shift coefficients were compared with the experimental data. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Investigation of interaction of carbon dioxide with aerogels nanopores

The absorption spectrum of 2 0 0 12 – 0 0 0 01 band of carbon dioxide, confined in 20 nm nanopores of silica aerogel, was measured with help of a Bruker IFS 125 HR Fourier transform spectrometer at room temperature and a spectral resolution of 0.01 cm-1. The obtained dependence of spectral line half-width values on rotational quantum numbers was studied and compared with data available in the literature. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Parameters of broadening of water molecule absorption lines by argon derived using different line profile models

The water vapor absorption spectrum was measured in the spectral region 6700–7650 cm–1 with argon as a buffer gas. The room-temperature spectrum was measured using a Bruker IFS 125-HR Fourier Transform Spectrometer with high signal-to-noise ratio, with a spectral resolution of 0.01 cm–1, at argon pressures from 0 to 0.9 atm. The H2O absorption spectral line parameters are derived by fitting two line shape profiles (Voigt and speed-dependent Voigt) to the experimental spectrum. It is shown that the use of speed-dependent Voigt profile provides the best agreement with experimental data

Modification of the experimental setup of the FTIR spectrometer and thirty-meter optical cell for measurements of weak selective and nonselective absorptions

The improvement of the experimental setup based on a Fourier spectrometer Bruker IFS-125 and a 30-meter multipass optical cell is described. The improvement includes the cell equipment with a system of automated adjustment of the number of beam passes without cell depressurization and ensures the cell work at high temperatures

Measurements with Pinhole and Coded Aperture Gamma-Ray Imaging Systems

From a safeguards perspective, gamma-ray imaging has the potential to reduce manpower and cost for effectively locating and monitoring special nuclear material. The purpose of this project was to investigate the performance of pinhole and coded aperture gamma-ray imaging systems at Oak Ridge National Laboratory (ORNL). With the aid of the European Commission Joint Research Centre (JRC), radiometric data will be combined with scans from a three-dimensional design information verification (3D-DIV) system. Measurements were performed at the ORNL Safeguards Laboratory using sources that model holdup in radiological facilities. They showed that for situations with moderate amounts of solid or dense U sources, the coded aperture was able to predict source location and geometry within ~7% of actual values while the pinhole gave a broad representation of source distribution

The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

Line mixing in some water vapor transitions perturbed by N2, Ar and He pressure

Line mixing effect has been studied for five pairs of H2O lines perturbed by N2, Ar and He. Two pairs of lines (in terms of the rotational quantum numbers J, Ka, and Kc) [1 0 1] ← [2 1 2], [2 1 2] ← [3 0 3] and [3 0 3] ← [2 1 2], [2 1 2] ← [1 0 1] belong to the ν2 band, two pairs of lines [3 1 2] ← [4 1 3], [3 2 1] ← [4 2 2] and [4 3 1] ← [3 3 0], [4 2 2] ← [3 2 1], belong to the ν1 + ν2 + ν3 band and fifth pair of the lines [5 4 1] ← [6 5 2], [5 4 1] ← [6 3 4] belong to the 3ν1 + ν2 and 8ν2 band, respectively. Pressure broadening coefficients of H2O (half-widths, pressure shifts and off-diagonal relaxation matrix elements) have been calculated for all lines and for two pair of lines from the ν1 + ν2 + ν3 band perturbed by N2 and Ar they have been obtained experimentally

Line mixing in some water vapor transitions perturbed by N2, Ar and He pressure

Line mixing effect has been studied for five pairs of H2O lines perturbed by N2, Ar and He. Two pairs of lines (in terms of the rotational quantum numbers J, Ka, and Kc) [1 0 1] ← [2 1 2], [2 1 2] ← [3 0 3] and [3 0 3] ← [2 1 2], [2 1 2] ← [1 0 1] belong to the ν2 band, two pairs of lines [3 1 2] ← [4 1 3], [3 2 1] ← [4 2 2] and [4 3 1] ← [3 3 0], [4 2 2] ← [3 2 1], belong to the ν1 + ν2 + ν3 band and fifth pair of the lines [5 4 1] ← [6 5 2], [5 4 1] ← [6 3 4] belong to the 3ν1 + ν2 and 8ν2 band, respectively. Pressure broadening coefficients of H2O (half-widths, pressure shifts and off-diagonal relaxation matrix elements) have been calculated for all lines and for two pair of lines from the ν1 + ν2 + ν3 band perturbed by N2 and Ar they have been obtained experimentally