0000000000147408

AUTHOR

Uldis Gross

Iodine and mercury resonance lamps for kinetics experiments and their spectra in the far ultraviolet

Electrodeless iodine and mercury iodide radio-frequency discharge lamps have been made to provide intense sources of resonance radiation of iodine and mercury in the 183-253 nm region. Production technology and emission spectra in the ultraviolet and vacuum ultraviolet regions are described. Both lamps (iodine and mercury iodide) are designed and used for monitoring the iodine 2P1/2 (206.163 nm) and 2P3/2 (183.038 nm) level population kinetics after flash photolysis of I2 or other precursor molecules in laboratory experiments. The technique is suitable for the investigation of the gas phase reaction kinetics following the photolysis of I2 in the presence of O3.

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Estimation of the emission temperature of an electrodeless discharge lamp and determination of the oscillator strength for the I(2P3/2) 183.038 nm resonance transition

Abstract The 183.038 nm resonance absorption transition of I( 2 P 3/2 ) has been studied using a flash photolysis set-up for gas-phase chemistry and a radio frequency powered electrodeless discharge lamp filled with iodine. The dependence of self-absorption and self-reversal on iodine partial pressure in the discharge volume was measured. The optimum iodine partial pressure, with self-absorption minimized and acceptable intensity, is determined to be approximately 2.5×10 −3 mbar. A method is described to estimate the temperature of the emitting atoms using direct measurements of relative absorption at different absorber concentrations. This yields an emission temperature of 923±50 K. Using …

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<title>Iodine and mercury resonance lamps and their spectrum in far UV</title>

Electrodeless iodine, mercury iodide, and mercury radio- frequency discharge lamps have been made to provide effective sources of atomic spectra for analytical spectroscopy providing powerful resonance radiation of iodine and mercury in the 120-253 nm region. The lamps are required and can be used for spectral calibration, resonance absorption, and fluorescence detection techniques, for investigation of atomic characteristics (e.g., branching ratios) and other purposes where intense monochromatic spectra are needed. Production technology, development, and investigation of the UV and VUV emission are described.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downlo…

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<title>Iodine and bromine resonance lamps in atmospheric research</title>

For the first time previously developed iodine resonance spectra source has been tested in flash photolysis experiment. Quantitative measurements of concentration kinetics of iodine atomic species in a I2+O3 system are possible. The 183.038 nm resonance absorption transition of I(2P3/2) in previously developed EDL has been studied; dependence of self-absorption and self-reversal on iodine partial pressure in the discharge volume has been measured. The search for optimal conditions for an iodine EDL with minimized self-absorption and sufficient intensity were made. In condition of flash photolysis with previously described method it is possible to determine the emission temperature, oscillat…

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A Ground Validation Station for the Satellite-based Atmospheric Sensor Instruments GOME and SCIAMACHY

The development of a DOAS based ground validation station for satellite based atmospheric sensor instruments GOME and SCIMACHY at the Institute of Atomic Physics and Spectroscopy, University of Latvia, is now underway. The activity has to look to the future by: — the development of co-operation with the European research community in atmospheric science contributing to the valuable infrastructure for common needs; and — a building up of the capacity of the team (through research training of students) to become a strong partner in the future.

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In situ detection of atomic and molecular iodine using resonance and off-resonance fluorescence by lamp excitation: ROFLEX

17 pags, 11 figs, 4 tabs

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