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Title: Laser-induced plasmas in air studied using two-color interferometry

Abstract

Temporally and spatially resolved density profiles of Cu atoms, electrons, and compressed air, from laser-induced copper plasmas in air, are measured using fast spectral imaging and two-color interferometry. From the intensified CCD images filtered by a narrow-band-pass filter centered at 515.32 nm, the Cu atoms expansion route is estimated and used to determine the position of the fracture surface between the Cu atoms and the air. Results indicate that the Cu atoms density at distances closer to the target (0–0.4 mm) is quite low, with the maximum density appearing at the edge of the plasma's core being ∼4.6 × 10{sup 24 }m{sup −3} at 304 ns. The free electrons are mainly located in the internal region of the plume, which is supposed to have a higher temperature. The density of the shock wave is (4–6) × 10{sup 25 }m{sup −3}, corresponding to air compression of a factor of 1.7–2.5.

Authors:
; ; ; ; ;  [1];  [2]
  1. State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Shaanxi 710049 (China)
  2. School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031 (China)
Publication Date:
OSTI Identifier:
22599900
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ATOMS; CHARGE-COUPLED DEVICES; COLOR; COMPRESSED AIR; COMPRESSION; COPPER; DENSITY; ELECTRONS; FILTERS; FRACTURES; IMAGES; INTERFEROMETRY; LASER-PRODUCED PLASMA; LASERS; PLUMES; SHOCK WAVES; SURFACES; TEMPERATURE RANGE 0400-1000 K

Citation Formats

Yang, Zefeng, Wu, Jian, E-mail: jxjawj@mail.xjtu.edu.cn, Li, Xingwen, Han, Jiaxun, Jia, Shenli, Qiu, Aici, and Wei, Wenfu. Laser-induced plasmas in air studied using two-color interferometry. United States: N. p., 2016. Web. doi:10.1063/1.4961086.
Yang, Zefeng, Wu, Jian, E-mail: jxjawj@mail.xjtu.edu.cn, Li, Xingwen, Han, Jiaxun, Jia, Shenli, Qiu, Aici, & Wei, Wenfu. Laser-induced plasmas in air studied using two-color interferometry. United States. doi:10.1063/1.4961086.
Yang, Zefeng, Wu, Jian, E-mail: jxjawj@mail.xjtu.edu.cn, Li, Xingwen, Han, Jiaxun, Jia, Shenli, Qiu, Aici, and Wei, Wenfu. 2016. "Laser-induced plasmas in air studied using two-color interferometry". United States. doi:10.1063/1.4961086.
@article{osti_22599900,
title = {Laser-induced plasmas in air studied using two-color interferometry},
author = {Yang, Zefeng and Wu, Jian, E-mail: jxjawj@mail.xjtu.edu.cn and Li, Xingwen and Han, Jiaxun and Jia, Shenli and Qiu, Aici and Wei, Wenfu},
abstractNote = {Temporally and spatially resolved density profiles of Cu atoms, electrons, and compressed air, from laser-induced copper plasmas in air, are measured using fast spectral imaging and two-color interferometry. From the intensified CCD images filtered by a narrow-band-pass filter centered at 515.32 nm, the Cu atoms expansion route is estimated and used to determine the position of the fracture surface between the Cu atoms and the air. Results indicate that the Cu atoms density at distances closer to the target (0–0.4 mm) is quite low, with the maximum density appearing at the edge of the plasma's core being ∼4.6 × 10{sup 24 }m{sup −3} at 304 ns. The free electrons are mainly located in the internal region of the plume, which is supposed to have a higher temperature. The density of the shock wave is (4–6) × 10{sup 25 }m{sup −3}, corresponding to air compression of a factor of 1.7–2.5.},
doi = {10.1063/1.4961086},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}
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