Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: BL Lacertae: the multiwavelength campaign of 2000   We present two BeppoSAX observations of BL Lacertae as part of a
multiwavelength radio-to-TeV campaign. During the first observation we observe
a faint Compton spectrum, while during the second, we detect a synchrotron
spectrum with the highest [2-10] keV flux ever measured; above 10 keV an
inverse Compton component begin to dominate. The synchrotron flux is very
variable with time scales of 1 hr. We describe four different SED shifting the
synchrotron peak both in frequency and flux intensity and we sketch a scenario
in which a blob moves along a jet and can be located in or outside the BLR.
This implies different radiative mechanism at work, SSC or external Compton,
producing different high energy spectra.

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The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
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The categories of this paper are: stat
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin