Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the deceleration of relativistic jets in active galactic nuclei I:
  Radiation drag   Deceleration of relativistic jets from active galactic nuclei (AGNs) detected
recently by MOJAVE team is discussed in connection with the interaction of the
jet material with the external photon field. Appropriate energy density of the
isotropic photon field which is necessary to decelerate jets is determined. It
is shown that the disturbances of the electric potential and magnetic surfaces
play important role in general dynamics of particle deceleration.

21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess