Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Correlation between the TeV and X-ray emission in high--energy peaked BL
  Lac objects   We discuss the correlation between the evolution of the TeV emission and
X-ray radiation observed in high-energy peaked BL Lac objects. We describe such
a correlation by a simple power law. In the first part of this work we present
correlations obtained for the activity of Mrk~501 observed in 1997 April and
for the activity of Mrk~421 observed in 2000 February. We also discuss results
of similar correlation obtained for this source by other authors. They report
an almost quadratic correlations observed between the evolution of the TeV and
X-ray emission. In the second part of this paper we present a phenomenological
model which describes the evolution of the synchrotron and inverse Compton
emission of a simple spherical homogeneous source. Neglecting the radiative
cooling of the particles we derive analytical expressions that describe the
evolution. Then we use a numerical code to investigate the impact of radiative
cooling on the evolution. The quadratic correlation observed during the decay
phase of the flare observed in Mrk~421 on 2001 March 19 appears problematic for
this basic modeling. The quadratic correlation can be explained only for
specific choices of the spectral bands used for the calculation. Therefore,
looking for more robust solutions, we investigate the evolution of the emission
generated by a cylindrical source. However this model does not provide robust
solutions for the problem of a quadratic correlation. factor. Finally we
briefly discuss the possible influence of the light travel time effect on our
results.

21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an