Plasma Decay of Nanosecond Pulsed Laser-Produced Ar and Ar-H2O Sparks at Atmospheric Pressure

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ahn, Ji Yung, Wang, Jianan, Faruquee, Tasnim Akbar, Simeni, Marien Simeni
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912845826883584
author Ahn, Ji Yung
Wang, Jianan
Faruquee, Tasnim Akbar
Simeni, Marien Simeni
author_facet Ahn, Ji Yung
Wang, Jianan
Faruquee, Tasnim Akbar
Simeni, Marien Simeni
contents Time-resolved diagnostics were applied to investigate free-electron properties in nanosecond laser-produced discharges sustained at atmospheric pressure in Ar and in Ar with 3% H2O. The discharges were generated using 23 ns, 1064 nm laser pulses. Broadband plasma imaging and laser Thomson scattering were combined with optical emission spectroscopy, with particular emphasis on Stark broadening of the Halpha and Hbeta lines. The plasma exhibited a bright emission that persisted for up to 30--40 us after breakdown, followed by a very weak glow lasting up to 19 ms. Peak electron number density of about 2 x 10^17 cm-3 and electron temperature of about 7 eV were measured. Excellent agreement between both techniques was obtained for absolute electron number densities. The inferred temporal decay of free electrons is consistent with processes dominated by ambipolar expansion and two- and three-body electron-ion recombination. These results provide benchmark data for modeling nanosecond laser discharges and demonstrate the reliability of combining Thomson scattering with Stark broadening in atmospheric laser sparks.
format Preprint
id arxiv_https___arxiv_org_abs_2601_17547
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Plasma Decay of Nanosecond Pulsed Laser-Produced Ar and Ar-H2O Sparks at Atmospheric Pressure
Ahn, Ji Yung
Wang, Jianan
Faruquee, Tasnim Akbar
Simeni, Marien Simeni
Plasma Physics
Optics
Time-resolved diagnostics were applied to investigate free-electron properties in nanosecond laser-produced discharges sustained at atmospheric pressure in Ar and in Ar with 3% H2O. The discharges were generated using 23 ns, 1064 nm laser pulses. Broadband plasma imaging and laser Thomson scattering were combined with optical emission spectroscopy, with particular emphasis on Stark broadening of the Halpha and Hbeta lines. The plasma exhibited a bright emission that persisted for up to 30--40 us after breakdown, followed by a very weak glow lasting up to 19 ms. Peak electron number density of about 2 x 10^17 cm-3 and electron temperature of about 7 eV were measured. Excellent agreement between both techniques was obtained for absolute electron number densities. The inferred temporal decay of free electrons is consistent with processes dominated by ambipolar expansion and two- and three-body electron-ion recombination. These results provide benchmark data for modeling nanosecond laser discharges and demonstrate the reliability of combining Thomson scattering with Stark broadening in atmospheric laser sparks.
title Plasma Decay of Nanosecond Pulsed Laser-Produced Ar and Ar-H2O Sparks at Atmospheric Pressure
topic Plasma Physics
Optics
url https://arxiv.org/abs/2601.17547