Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Supernova Remnants as the Sources of Galactic Cosmic Rays   The origin of cosmic rays holds still many mysteries hundred years after they
were first discovered. Supernova remnants have for long been the most likely
sources of Galactic cosmic rays. I discuss here some recent evidence that
suggests that supernova remnants can indeed efficiently accelerate cosmic rays.
For this conference devoted to the Astronomical Institute Utrecht I put the
emphasis on work that was done in my group, but placed in a broader context:
efficient cosmic-ray acceleration and the im- plications for cosmic-ray escape,
synchrotron radiation and the evidence for magnetic- field amplification,
potential X-ray synchrotron emission from cosmic-ray precursors, and I conclude
with the implications of cosmic-ray escape for a Type Ia remnant like Tycho and
a core-collapse remnant like Cas A.

32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph