Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Supernova remnants with magnetars: clues to magnetar formation   I discuss the lack of observational evidence that magnetars are formed as
rapidly rotating neutron stars. Supernova remnants containing magnetars do not
show the excess of kinetic energy expected for such a formation scenario, nor
is there any evidence for a relic pulsar wind nebula. However, it could be that
magnetars are formed with somewhat slower rotation periods, or that not all
excess rotational energy was used to boost the explosion energy, for example as
a result of gravitational radiation. Another observational tests for the rapid
initial period hypothesis is to look for statistical evidence that about 1% of
the observed supernovae have an additional 1E40-1E44 erg/s excess energy during
the first year, caused by the spin down luminosity of a magnetar. An
alternative scenario for the high magnetic fields of magnetars is the fossil
field hypothesis, in which the magnetic field is inherited from the progenitor
star. Direct observational tests for this hypothesis are harder to formulate,
unless the neutron star formed in the SN1987A explosion emerges as a slowly
rotating magnetar. Finally, I point out the possible connection between the
jets in Cas A and its X-ray point source: the jets in Cas A may indicate that
the explosion was accompanied by an X-ray flash, probably powered by a rapidly
rotating compact object. However, the point source in Cas A does not seem to be
a rapidly rotating neutron star, suggesting that the neutron star has slowed
down considerably in 330 yr, requiring a magnetar-like field.

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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat