Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Negative-ion surface production in hydrogen plasmas: Determination of
  the negative-ion energy and angle distribution function using mass
  spectrometry   This work focuses on the understanding of the production mechanism of
negative-ions on surface in low pressure plasmas of H2/D2. The negative ions
are produced on a HOPG sample (Highly Oriented Pyrolitic Graphite) negatively
biased with respect to plasma potential. The negative ions created under the
positive ion bombardment are accelerated towards the plasma, self-extracted and
detected according to their energy and mass by a mass spectrometer placed in
front of the sample. The shape of the measured Negative-Ion Energy Distribution
Function (NIEDF) strongly differs from the NIEDF of the ions emitted by the
sample because of the limited acceptance angle of the mass spectrometer. To get
information on the production mechanisms, we propose a method to obtain the
distribution functions in energy and angle (NIEADFs) of the negative-ions
emitted by the sample. It is based on an a priori determination of the NIEADF
and on an a posteriori validation of the choice by comparison of the modelled
and experimental NIEDFs.

36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph