Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Sources of Apparently Non-Repeating FRB   There are insufficient catastrophic events (collapse, explosion or merger of
stars or compact objects) to explain the cosmologically local rate of
apparently non-repeating FRB if each such catastrophic event produces a single
FRB. Unless produced by some novel and unsuspected but comparatively frequent
event, apparently non-repeating FRB must actually repeat many times in the
lifetimes of their sources. Yet no such infrequent repetitions (in contrast to
the frequent activity of FRB known to repeat) have been observed, constraining
their repetition rates and active lifetimes. The absence of more frequent
weaker but detectable repetitive outbursts in apparent non-repeaters resembles
the distribution of SGR outbursts, with a large gap between giant outbursts and
lesser outbursts. This suggests mini-SGR as sources, more energetic than SGR
1935$+$2154 associated with FRB 200428 but less energetic than SGR 1806$-$20
that had no associated FRB. Their largest radio outbursts would, at
cosmological distances, be apparently non-repeating FRB and their X-ray and
gamma-ray outbursts would be undetectable. The large gap between the strongest
outburst of FRB 200428 and its lesser outbursts resembles the gamma-ray
properties of individual well-observed SGR; at twenty times its actual
distance, FRB 200428 would have been an apparent non-repeater.

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The categories of this paper are: hep-ex
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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: math
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The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex