Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generation of high-energy electron-positron beams in the collision of a
  laser-accelerated electron beam and a multi-petawatt laser   Generation of antimatter via the multiphoton Breit-Wheeler process in an
all-optical scheme will be made possible on forthcoming high-power laser
facilities through the collision of wakefield-accelerated GeV electrons with a
counter-propagating laser pulse with $10^{22}$-$10^{23}$ $\mathrm{Wcm}^{-2}$
peak intensity. By means of integrated 3D particle-in-cell simulations, we show
that the production of positron beams with 0.1-1 nC total charge, 100-400 MeV
mean energy and 0.01-0.1 rad divergence is within the reach of
soon-to-be-available laser systems. The variations of the positron beam's
properties with respect to the laser parameters are also examined.

19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga