Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improvement of solar cycle prediction: Plateau of solar axial dipole
  moment   Aims. We report the small temporal variation of the axial dipole moment near
the solar minimum and its application to the solar cycle prediction by the
surface flux transport (SFT) model. Methods. We measure the axial dipole moment
using the photospheric synoptic magnetogram observed by the Wilcox Solar
Observatory (WSO), the ESA/NASA Solar and Heliospheric Observatory Michelson
Doppler Imager (MDI), and the NASA Solar Dynamics Observatory Helioseismic and
Magnetic Imager (HMI). We also use the surface flux transport model for the
interpretation and prediction of the observed axial dipole moment. Results. We
find that the observed axial dipole moment becomes approximately constant
during the period of several years before each cycle minimum, which we call the
axial dipole moment plateau. The cross-equatorial magnetic flux transport is
found to be small during the period, although the significant number of
sunspots are still emerging. The results indicates that the newly emerged
magnetic flux does not contributes to the build up of the axial dipole moment
near the end of each cycle. This is confirmed by showing that the time
variation of the observed axial dipole moment agrees well with that predicted
by the SFT model without introducing new emergence of magnetic flux. These
results allows us to predict the axial dipole moment in Cycle 24/25 minimum
using the SFT model without introducing new flux emergence. The predicted axial
dipole moment of Cycle 24/25 minimum is 60--80 percent of Cycle 23/24 minimum,
which suggests the amplitude of Cycle 25 even weaker than the current Cycle 24.
Conclusions. The plateau of the solar axial dipole moment is an important
feature for the longer prediction of the solar cycle based on the SFT model.

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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
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The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
9
The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: q-bio