Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Speed of Meridional Flows and Magnetic Flux Transport on the Sun   We use the magnetic butterfly diagram to determine the speed of the magnetic
flux transport on the solar surface towards the poles. The manifestation of the
flux transport is clearly visible as elongated structures extended from the
sunspot belt to the polar regions. The slopes of these structures are measured
and interpreted as meridional magnetic flux transport speed. Comparison with
the time-distance helioseismology measurements of the mean speed of the
meridional flows at the depth of 3.5--12 Mm shows a generally good agreement,
but the speeds of the flux transport and the meridional flow are significantly
different in areas occupied by the magnetic field. The local circulation flows
around active regions, especially the strong equatorward flows on the
equatorial side of active regions affect the mean velocity profile derived by
helioseismology, but do not influence the magnetic flux transport. The results
show that the mean longitudinally averaged meridional flow measurements by
helioseismology may not be used directly in solar dynamo models for describing
the magnetic flux transport, and that it is necessary to take into account the
longitudinal structure of these flows.

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The categories of this paper are: funct-an
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph