Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Arc temperatures in a circuit breaker experiment from iterative analysis
  of emission spectra   A switching-off process very similar to those in real high-voltage self-blast
circuit-breakers is emulated in a model chamber to study the arc properties by
optical emission spectroscopy. The arc is operated in a chamber filled with
SF$_6$ between a pin-tulip contact system enclosed by a PTFE nozzle.
Transparent windows in the chamber wall and a slit in the nozzle enable an
optical investigation of the arc cross section less than one millisecond before
current zero. The side-on radiance of a fluorine atom lines has been measured
with an imaging spectroscopic system. Considering rotational symmetry of the
arc the corresponding radial emission coefficients have been determined by Abel
inversion. The radial temperature profiles are calculated from the emission
coefficients including pressure measurements and the corresponding plasma
composition. In contrast to previous studies, a specific iterative approach is
proposed to consider the optical thickness of the plasma. A maximum optical
thickness between 0.2 and 0.4 has been observed. Temperature profiles corrected
for absorption effects show increasing maximum temperature in the arc axis with
decreasing current towards current zero. The effect of the plasma composition
on absolute arc temperatures is discussed. The temperature profiles can be used
to validate CFD simulations of the switching-off process in the model chamber.

22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph