Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultrafast target charging due to polarization triggered by
  laser-accelerated electrons   A significant step has been made towards understanding the physics of the
transient surface current triggered by ejected electrons during the interaction
of a short intense laser pulse with a high-conductivity target. Unlike the
commonly discussed hypothesis of neutralization current generation as a result
of the fast loss of hot electrons to the vacuum, the proposed mechanism is
associated with excitation of the fast current by electric polarization due to
transition radiation triggered by ejected electrons. We present a corresponding
theoretical model and compare it with two simulation models using the FDTD
(finite-difference time-domain) and PIC (particle-in-cell) methods. Distinctive
features of the proposed theory are clearly manifested in both of these models.

17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga