Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Space charge limited flow of a thin electron beam confined by a strong
  magnetic field   An approximate analytic theory is developed and implemented numerically for
calculating the space charge limited current and electric field of a thin
cylindrical beam or current sheet between two wide parallel electrodes. The
flow is confined by a sufficiently strong magnetic field. Assuming that the
potential and current density are almost homogeneous in the direction
transversal to the flow we compute the beam current and profile by a
variational method. We find that the average current density scales as the
reciprocal of the beam width when the latter becomes very small. The total
cylindrical beam current thus decreases proportionly to its diameter while the
total current of a sheet becomes almost independent of the width in this
regime.

26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
1
The categories of this paper are: cs