Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unusual migration of the prominence activities in the southern
  hemisphere during Cycle 23--24   The solar activity in Cycle 23--24 shows differences from the previous cycles
that were observed with modern instruments, e.g. long cycle duration and a
small number of sunspots. To appreciate the anomalies further, we investigated
the prominence eruptions and disappearances observed with the Nobeyama
Radioheliograph during over 20 years. Consequently, we found that the
occurrence of the prominence activities in the northern hemisphere is normal
because the period of the number variation is 11 years and the migration of the
producing region of the prominence activities traces the migration of 11 years
ago. On the other hand, the migration in the southern hemisphere significantly
differs from that in the northern hemisphere and the previous cycles. The
prominence activities occurred over -50 degrees latitude in spite of the late
decay phase of Cycle 23, and the number of the prominence activities in the
higher latitude region (over -65 degrees) is very small even near the solar
maximum of Cycle 24. The results suggest that the anomalies of the global
magnetic field distribution started at the solar maximum of Cycle 23.
Comparison of the butterfly diagram of the prominence activities with the
magnetic butterfly diagram indicates that the timing of "the rush to the pole"
and the polar magnetic field closely relates to the unusual migration.
Considering that the rush to the pole is made of the sunspots, the hemispheric
asymmetry of the sunspots and the strength of the polar magnetic fields are
essential for understanding the anomalies of the prominence activities.

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The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys