N. Bashlov et al., SIMULATION OF THE HIGH-PRESSURE MERCURY DISCHARGE LAMP DURING THE MIDDLE PHASE OF START-UP (MEDIUM MERCURY PRESSURE), Journal of physics. D, Applied physics, 27(3), 1994, pp. 494-503
This paper deals with the modelling of the medium pressure Hg and Hg-A
r positive column (Hg pressure range 5-350 Torr). The aim of this work
is to simulate, in a first approximation, the middle phase of the Hg
high-pressure lamp warm-up. In this approach, the main assumption is t
hat time evolution of the discharge can be divided into a succession o
f stationary sub-phases characterized by the Hg partial pressure. Thus
, we present here a self-consistent steady-state collisional-radiative
model describing the middle sub-phase. This model includes volume rec
ombination of Hg atomic and molecular ions, as well as several atom-at
om inelastic scattering mechanisms. Calculations are carried out for b
oth pure Hg and Hg-Ar discharges. Our results, which are in good agree
ment with experimental data from the literature, confirm that plasma t
hermalization occurs in the middle start-up phase (electron and gas te
mperatures become equal during this phase). Furthermore, this simulati
on shows the importance of different elementary processes, like atom-a
tom inelastic scattering, for the medium pressure plasma description.
In fact, these mechanisms cannot be neglected until LTE conditions are
reached.