Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sun's Seismic Radius as Measured from the Fundamental Modes of
  Oscillations and its Implications for the TSI Variations   In this letter, we explore the relationship between the solar seismic radius
and total solar irradiance (TSI) during last two solar cycles using the
uninterrupted data from space-borne instruments onboard {\it SoHO} and {\it
SDO}. The seismic radius is calculated from the fundamental ({\it f}) modes of
solar oscillations utilizing the observations from {\it SoHO}/MDI and {\it
SDO}/HMI, and the total solar irradiance measurements are obtained from {\it
SoHO}/VIRGO. Our study suggests that the major contribution to the TSI
variation arises from the changes in magnetic field while the radius variation
plays a secondary role. We find that the solar irradiance increases with
decreasing seismic radius, however the anti-correlation between them is
moderately weak. The estimated maximum change in seismic radius during a solar
cycle is about 5 kilometers, and is consistent in both solar cycles 23 and 24.
Previous studies suggest a radius change at the surface of the order of 0.06
arcsecond to explain the 0.1\% variation in the TSI values during the solar
cycle, however our inferred seismic radius change is significantly smaller,
hence the TSI variations can not be fully explained by the temporal changes in
seismic radius.

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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg