Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic fields and star formation in spiral galaxies   The main observational results from radio continuum and polarization
observations about the magnetic field strength and large-scale pattern for
face-on and edge-on spiral galaxies are summarized and compared within our
sample of galaxies of different morphological types, inclinations, and star
formation rates (SFR). We found that galaxies with low SFR have higher thermal
fractions/smaller synchrotron fractions than those with normal or high SFR.
Adopting an equipartition model, we conclude that the nonthermal radio emission
and the \emph{total magnetic field} strength grow nonlinearly with SFR, while
the regular magnetic field strength does not seem to depend on SFR. We also
studied the magnetic field structure and disk thicknesses in highly inclined
(edge-on) galaxies. We found in four galaxies that - despite their different
radio appearance - the vertical scale heights for both, the thin and thick
disk/halo, are about equal (0.3/1.8 kpc at 4.75 GHz), independently of their
different SFR. This implies that all these galaxies host a galactic wind, in
which the bulk velocity of the cosmic rays (CR) is determined by the total
field strength within the galactic disk. The galaxies in our sample also show a
similar large-scale magnetic field configuration, parallel to the midplane and
X-shaped further away from the disk plane, independent of Hubble type and SFR
in the disk. Hence we conclude that also the large-scale magnetic field pattern
does not depend on the amount of SFR.

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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: econ
10
The categories of this paper are: q-bio
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The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci