Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coherent photon-photon interactions in very peripheral relativistic
  heavy ion collisions   Heavy ions at high velocities provide very strong electromagnetic fields for
a very short time. The main characteristics of ultraperipheral relativistic
heavy ion collisions are reviewed, characteristic parameters are identified.
The main interest in ultraperipheral heavy ion collisions at relativistic ion
colliders like the LHC is the interactions of very high energy (equivalent)
photons with the countermoving (equivalent) photons and hadrons (protons/ions).
The physics of these interactions is quite different from and complementary to
the physics of the strong fields achieved with current and future lasers.

3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph