Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transient Hollow Cathode Effects and Z pinch Formation in a High Current
  Capillary Discharge with a Metal Plasma   The results from a series of experiments are presented whose purpose is to
explore different schemes which may lead to the formation of pure metal plasmas
in a capillary discharge with parameters appropriate for X ray lasing. The
experiments were performed in ceramic wall capillary discharges at currents of
up to 120 kA, with an available ID of between 3 and 8 mm and with lengths from
60 to 100 mm. Initial plasma conditions in the capillary exploit transient
hollow cathode effects in a preionizing discharge. A laser focussed onto the
back surface of the cathode initiates both beam activity in the capillary
volume and plasma injection. To promote metal ablation into the pinch channel
of elements other than the ceramic wall material, a number of graded ring
schemes have been tried. The plasma is observed axially using both time and
energy resolved soft X-ray pin hole images as well as from time resolved soft
X-ray spectra. By varying the rate of rise of the current of the main
discharge, and the preionizing conditions the diameter and the stability of the
Z-pinch column are seen to be affected. The ratio of the species from the
ablated wall material to the plasma formed from the graded ring structure is
found to depend both on the capillary dimensions as well as the other operating
conditions.

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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
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The categories of this paper are: math
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The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
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The categories of this paper are: cs
0
The categories of this paper are: hep-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int