Characteristics of moderate current vacuum discharge triggered by multipicosecond and nanosecond duration laser pulses

Journal Article · Tue Feb 15 04:00:00 EST 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1848189· OSTI ID:20668204

Moorti, A; Kumbhare, S R; Naik, P A; Gupta, P D; Romanov, I V; Korobkin, Yu V; Rupasov, A A; Shikanov, A S ^[1]

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1. Laser Plasma Division, Centre for Advanced Technology, Indore 452013 (India)

A comparative study of the characteristics of moderate-current ({approx}10 kA), low-energy ({<=}20 J) vacuum discharge triggered by multipicosecond and nanosecond duration laser pulses is performed. Temporal profiles of the x-ray emission, discharge current, and anode voltage measured in vacuum discharge created between a planar titanium cathode and a conical point-tip anode are observed to be quite different for the two regimes of the laser pulse duration. While cathode plasma jet pinching is clearly observed in the discharge created by low-energy ({approx}5 mJ), 27 ps full width at half-maximum (FWHM) laser pulses, a feeble pinching occurred for 4 ns (FWHM) laser pulses only above a threshold energy of {approx}250 mJ. In addition to the multiple K-shell x-ray pulses emitted from the titanium anode up to 100 ns, evidence of a much harder x-ray component (h{nu}>100 keV) is also seen in the discharge triggered by picosecond laser pulses.

• OSTI ID: 20668204
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 4 Vol. 97; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANODES
CATHODES
ELECTRIC POTENTIAL
EMISSION
HARD X RADIATION
K SHELL
KEV RANGE 100-1000
LASER-PRODUCED PLASMA
LASERS
PINCH EFFECT
PLASMA JETS
PLASMA PRODUCTION
PULSES
THERMIONIC DIODES
THRESHOLD ENERGY
TITANIUM
VELOCITY