Original scientific paper

Avalanche spark breakdown in Ne-Br2

Z. Šternberg ; Institute "Ruđer Bošković", Zagreb
V. Henč-Bartolić ; Institute "Ruđer Bošković", Zagreb

Abstract

The properties of an avalanche spark in Ne-Br2 mixtures and parallel plate geometry are discussed. Intense spectral emission of the Br2 lg {3 II lg) → 2u {3Δ2u) bands, which persists a few μs during afterglow, is observed. Evidence is obtained also of imprisonment of the Nel resonance radiation. The influence of various processes on the current buildup is considered, and the observed high rate of current growth is attributed primarily to Penning ionization of bromine and to U. V. radiation emitted by Br'2 molecules. With discharging of the plates the initially negative characteristic changes its sign, and the plates may be discharged to voltages as low as 25 - 30 V; it is suggested that delayed photons are responsible for the observed effect. During the first microsecond after the onset of the spark breakdown the entire cathode surface is covered by a space charge zone. With prolongation of the pulse the cathode spot contracts both axially and radially, and a normal glow discharge is established within 20 - 50 μs according to the circuit parameters, gas composition, and the initial voltage. The contraction mechanism is briefly discussed.

Keywords

Hrčak ID:

320127

URI

https://hrcak.srce.hr/320127

Publication date:

7.6.1970.

Article data in other languages: croatian

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