skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Collision Broadening Of Line Spectrum In Sonoluminescence

Abstract

The direct measurement of temperature inside a sonoluminescing bubble as it is at its flashing phase is almost impossible due to the smallness of the bubble and the short duration of the flashing. One may estimate the temperature through fitting the continuum spectrum of sonoluminescence by the black body radiation formula, or fitting the shape of atomic or molecular line spectrum (the different temperature, density and pressure result in the different shape of the line spectrum due to the effect of collision broadening). However, the temperature changes in a huge range at short duration as the bubble flashes, therefore, the observed spectra are some kind of average one, so are those fitted results. To evaluate the instantaneous temperature more accurately, we simulate the processes of the bubble motion and the thermodynamics inside the bubble, in which atomic or molecular line spectra with the collision broadening effect and the continuum spectra contributed from the processes of electron-atom bremsstrahlung, electron-ion bremsstrahlung and recombination radiation and radiative attachment of electrons to atoms and molecules are taken into account in calculating the light emission. If both the calculated continuum spectra and the shape of line spectra can well represent the experimental data, we maymore » deduce that the calculation of the temperature, density and pressure is reliable and we indirectly evaluate those quantities inside the bubble. In the present calculation, the line spectra of OH radical at about 310 nm mixing the electron transition with the vibration and rotational bands are considered. The calculation qualitatively consists with the observation, and we expect that with the more precise bubble dynamics model instead of the uniform model employed in the present calculation we may improve the quantitative result.« less

Authors:
 [1];  [1];  [2]
  1. Department of Physics, Tsinghua University, Beijing 100084 (China)
  2. (China)
Publication Date:
OSTI Identifier:
21148816
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1022; Journal Issue: 1; Conference: ISNA 18: 18. international symposium on nonlinear acoustics, Stockholm (Sweden), 7-10 Jul 2008; Other Information: DOI: 10.1063/1.2956181; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ACOUSTICS; ATOMS; BLACKBODY RADIATION; BREMSSTRAHLUNG; BUBBLES; ELECTRON ATTACHMENT; ELECTRON COLLISIONS; ELECTRONS; HYDROXYL RADICALS; IONS; LINE BROADENING; LUMINESCENCE; MOLECULES; NONLINEAR PROBLEMS; RECOMBINATION; ROTATIONAL STATES; TEMPERATURE MEASUREMENT; VIBRATIONAL STATES

Citation Formats

Li Chaohui, An Yu, and Institute of Acoustics, Chinese Academy of Science, Beijing 100080. Collision Broadening Of Line Spectrum In Sonoluminescence. United States: N. p., 2008. Web. doi:10.1063/1.2956181.
Li Chaohui, An Yu, & Institute of Acoustics, Chinese Academy of Science, Beijing 100080. Collision Broadening Of Line Spectrum In Sonoluminescence. United States. doi:10.1063/1.2956181.
Li Chaohui, An Yu, and Institute of Acoustics, Chinese Academy of Science, Beijing 100080. 2008. "Collision Broadening Of Line Spectrum In Sonoluminescence". United States. doi:10.1063/1.2956181.
@article{osti_21148816,
title = {Collision Broadening Of Line Spectrum In Sonoluminescence},
author = {Li Chaohui and An Yu and Institute of Acoustics, Chinese Academy of Science, Beijing 100080},
abstractNote = {The direct measurement of temperature inside a sonoluminescing bubble as it is at its flashing phase is almost impossible due to the smallness of the bubble and the short duration of the flashing. One may estimate the temperature through fitting the continuum spectrum of sonoluminescence by the black body radiation formula, or fitting the shape of atomic or molecular line spectrum (the different temperature, density and pressure result in the different shape of the line spectrum due to the effect of collision broadening). However, the temperature changes in a huge range at short duration as the bubble flashes, therefore, the observed spectra are some kind of average one, so are those fitted results. To evaluate the instantaneous temperature more accurately, we simulate the processes of the bubble motion and the thermodynamics inside the bubble, in which atomic or molecular line spectra with the collision broadening effect and the continuum spectra contributed from the processes of electron-atom bremsstrahlung, electron-ion bremsstrahlung and recombination radiation and radiative attachment of electrons to atoms and molecules are taken into account in calculating the light emission. If both the calculated continuum spectra and the shape of line spectra can well represent the experimental data, we may deduce that the calculation of the temperature, density and pressure is reliable and we indirectly evaluate those quantities inside the bubble. In the present calculation, the line spectra of OH radical at about 310 nm mixing the electron transition with the vibration and rotational bands are considered. The calculation qualitatively consists with the observation, and we expect that with the more precise bubble dynamics model instead of the uniform model employed in the present calculation we may improve the quantitative result.},
doi = {10.1063/1.2956181},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1022,
place = {United States},
year = 2008,
month = 6
}
  • An experimental investigation was made of the impact (collision) broadening and shift of a mercury laser emission line representing the 6p'more » $sup 3$P$sup 0$$sub 2$$Yields$7s$sup 3$S$sub 1$ (lambda=1.53 $mu$) transition as a function of helium and neon pressures. The boradening of the mercury line varied at a rate of 16 MHz/mm Hg with the helium pressure and at a rate of 10.5 MHz/mm Hg with the neon pressure. Direct measurements indicated that the line was shifted in the direction of the violet side of the spectrum. The rate of shift with the helium pressure was 1.8 MHz/mm Hg and that with the neon pressure was 1.2 MHz/mm Hg. A comparison of the Hg--He and Hg--Ne interactions indicated that in both cases this interaction was the same and was described by the Lennard-- Jones potential. Simultaneous measurements of the broadening and shift gave the values of the phenomenological constants C$sub 6$ and C$sub 12$, whose orders of magnitude were in agreement with the impact (collision) theory. An estimate was obtained of the lifetime of the 6p'$sup 3$P$sup 0$$sub 2$ level, which was approx.2times10$sup -7$ sec.« less
  • The temperature dependence of the collision broadening of the spectrum of the {sup 2}P{sub 1/2} {yields} {sup 2}P{sub 3/2} line of atomic iodine is determined in the 220 - 347 K range by the technique of high-resolution diode laser spectroscopy. The collision width in an oxygen-nitrogen medium depends on temperature as (300 K/T){sup {gamma}}, where {gamma}=0.87 {+-} 0.13. (laser applications and other topics in quantum electronics)
  • Wall-collision broadening of near-infrared absorption lines of molecular oxygen confined in nanoporous zirconia is studied by employing high-resolution diode-laser spectroscopy. The broadening is studied for pores of different sizes under a range of pressures, providing new insights on how wall collisions and intermolecular collisions influence the total spectroscopic line profile. The pressure series show that wall-collision broadening is relatively more prominent under reduced pressures, enabling sensitive means to probe pore sizes of porous materials. In addition, we show that the total wall-collision-broadened profile strongly deviates from a Voigt profile and that wall-collision broadening exhibits an additive-like behavior to the pressuremore » and Doppler broadening.« less