Search results for "Fourier transform spectrometers"
showing 6 items of 6 documents
Line intensities of CH3D in the Triad region: 6–10μm
2004
Abstract Line intensities of the three lowest fundamentals of the 12CH3D Triad are modeled with an RMS of 3.2% using over 2100 observed values retrieved by multispectrum fitting of enriched sample spectra recorded with two Fourier transform spectrometers. The band strengths of the Triad in units of 10−18 cm−1/(molecule cm−2) at 296 K are, respectively, 2.33 for ν6 (E) at 1161 cm−1, 1.75 for ν3 (A1) at 1307 cm−1 and 0.571 for ν5 (E) at 1472 cm−1. The total calculated absorption arising from 12CH3D Triad fundamentals is 4.65×10−18 cm−1/(molecule cm−2) at 296 K. In addition, some 740 intensities of nine hotbands are fitted to 8.1%; most of the hotband measurements belong to 2ν6−ν6 and ν3+ν6−ν3…
Methane and carbon monoxide infrared emissions observed at the Canada-France-Hawaii Telescope during the collision of comet SL-9 with Jupiter
1995
Observations with the Fourier Transform Spectrometer were conducted in spectral ranges from 1.6 to 4.7 µm from July 17 to 21 (UT) on the hot plumes appearing on the limb as well as hours or days after the impacts. We present here an analysis of the methane emission observed at 3.3 µm some 10 min after the C impact, indicating the presence of a very small (less than 100 km wide) hot region with temperatures in the 750–1500 K range within the 0.1- to 0.01-mbar region. We also report the detection of CO emission at 4.7 µm 4.5 hrs after the L impact, indicative of a temperature of 274±10 K at the ∼1016 CO molec cm−2 level. The observations suggest that the stratospheric temperature decreases wi…
High resolution study of AsHD2: Ground state and the three bending fundamental bands v(3), v(4), and v(6)
2006
International audience; For the first time the infrared spectrum of the AsHD2 molecule has been measured in the region of the bending fundamental bands v(3), v(4), and v(6) on a Fourier transform spectrometer with a resolution of 0.0024 cm(-1) and analyzed. More than 5500 transitions with J(max) = 26 have been assigned and used both to obtain "ground state combination differences" and for the determination of upper state ro-vibrational energies of the triad (001000), (000100), and (000001). Rotational parameters including centrifugal distortion coefficients up to octic terms of the ground vibrational state were calculated by fitting more than 500 "ground state combination differences" with …
Direct excitation of the “dark”b3Πstate predicted by deperturbation analysis of theA1Σ+−b3Πcomplex in KCs
2010
The diode-laser-induced fluorescence spectra $b {}^{3}{\ensuremath{\Pi}}_{\ensuremath{\Omega}=0}^{+}\ensuremath{\rightarrow}{X}^{ 1}{\ensuremath{\Sigma}}^{+}$ originated from the rovibronic levels of the ``dark'' triplet $b {}^{3}{\ensuremath{\Pi}}_{\ensuremath{\Omega}=0}^{+}$ state of KCs dimers were recorded with a Fourier transform spectrometer with a resolution of 0.03 cm${}^{\ensuremath{-}1}$. Term values of 30 rovibronic levels $({v}_{b0}^{*}\ensuremath{\in}[14,18];{J}^{\ensuremath{'}}\ensuremath{\in}[47,134])$ below the minimum of perturbing $A {}^{1}{\ensuremath{\Sigma}}^{+}$ state were determined with 0.003--0.01 cm${}^{\ensuremath{-}1}$ uncertainty. The optimal excitation and dete…
Linestrengths of the ν2 and ν4 bands of 12CH4 and 13CH4
1989
Absorption spectra recorded on the high-resolution Fourier transform spectrometer at Kitt Peak National Observatory/National Solar Observatory were used to measure individual line strengths of the nu(2) and nu(4) bands of (C-12)H4 and (C-13)H4. The measurements were used to obtain expressions that could be used to correctly predict individual line strengths through five orders of magnitude of absorption strength and high values of J-prime. Transition strengths were modeled using the dyad formalism of two interacting bands and a seven-term second-order dipole-moment expansion. The successful fitting of these data indicates that the method can be used to model measurements of 2- to 5-percent …
Deconvolution of Multiple Spectral Lines Shapes by Means of Tikhonov’s Regularization Method
2013
We present deconvolution of multiple narrow Zeeman split Hg lines, emitted from Hg/Xe micro-size capillary and measured by the Fourier Transform spectrometer. The ill-posed inverse problem was solved using the Tikhonov& rsquo;s regularization method.