Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing the Pulsar Wind Nebula of PSR B0355+54   We present XMM-Newton and Chandra X-ray observations of the middle-aged radio
pulsar PSR B0355+54. Our X-ray observations reveal emission not only from the
pulsar itself, but also from a compact diffuse component extending ~50'' in the
opposite direction to the pulsar's proper motion. There is also evidence for
the presence of fainter diffuse emission extending ~5' from the point source.
The compact diffuse feature is well-fitted with a power-law, the index of which
is consistent with the values found for other pulsar wind nebulae. The
morphology of the diffuse component is similar to the ram-pressure confined
pulsar wind nebulae detected for other sources. The X-ray emission from the
pulsar itself is described well by a thermal plus power-law fit, with the
thermal emission most likely originating in a hot polar cap.

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The categories of this paper are: cs
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The categories of this paper are: atom-ph
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The categories of this paper are: nlin
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: adap-org
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: acc-phys