Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Seismo-ionospheric effects associated with 'Chelyabinsk' meteorite
  during the first 25 minutes after its fall   This paper presents the properties of ionospheric irregularities elongated
with Earth magnetic field during the first 25 minutes after the fall of the
meteorite 'Chelyabinsk' experimentally observed with EKB radar of Russian
segment of the SuperDARN.
  It is shown that 40 minutes before meteor fall the EKB radar started to
observe powerful scattering from irregularities elongated with the Earth
magnetic field in the F-layer. Scattering was observed for 80 minutes and
stopped 40 minutes after the meteorite fall.
  During 9-15 minutes after the meteorite fall at ranges 400-1200 km from the
explosion site a changes were observed in the spectral and amplitude
characteristics of the scattered signal. This features were the sharp increase
in the Doppler frequency shift of the scattered signal corresponding to the
Doppler velocities about 600 m/s and the sharp increase of the scattered signal
amplitude. This allows us to conclude that we detected the growth of
small-scale ionospheric irregularities elongated with the Earth magnetic field
at E-layer heights. Joint analysis with the seismic data and numerical modeling
shows that the observed effect is connected with the passage of secondary
acoustic front formed by supersonic seismic ground wave from the 'Chelyabinsk'
meteorite.
  As a possible explanation the growth of elongated ionospheric irregularities
may be caused by the passage of the high-speed acoustic wave in the ionosphere
in the presence of high enough background electric field.

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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ph
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: math
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The categories of this paper are: eess