Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron cyclotron resonance discharge as a source for hydrogen and
  deuterium ions production   In this report, we describe characteristics of a ring-structure hydrogen
plasma heated in electron cyclotron resonance conditions and confined in a
mirror magnetic trap and discuss the relative efficiency of secondary electrons
and thermoelectrons in negative hydrogen and deuterium ion production. The
obtained data and calculations of the balance equations for possible reactions
demonstrate that the negative ion production is realized in two stages. First,
the hydrogen and deuterium molecules are excited in collisions with the plasma
electrons to high-laying Rydberg or vibrational levels in the plasma volume.
The second stage leads to the negative ion production through the process of
dissociative attachment of low energy electrons. The low energy electrons are
originated due to a bombardment of the plasma electrode by ions of one of the
driven rings and thermoemission from heated tungsten filaments. Experiments
seem to indicate that the negative ion generation occurs predominantly in the
limited volume filled with thermoelectrons. Estimation of the negative ion
generation rate shows that the main channel of and ion production involves the
process of high Rydberg state excitation.

13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin