Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurements of atmospheric turbulence parameters at Vainu Bappu
  Observatory using short-exposure CCD images   We report the atmospheric turbulence parameters namely, atmospheric seeing,
the tilt-anisoplanatic angle ($\theta_0$) and the coherence time ($\tau_0$),
measured under various sky conditions, at Vainu Bappu Observatory in Kavalur.
Bursts of short exposure images of selected stars were recorded with a
high-speed, frame-transfer CCD mounted on the Cassegrain focus of a newly
commissioned 1.3 m telescope. The estimated median seeing is $ \approx
1.85^{\prime\prime} $ at wavelength of $\sim 600$ nm, the image motion
correlation between different pairs of stars is $\sim 44\%$ for $\theta_0
\approx 36^{\prime\prime}$ and mean $\tau_0$ is $\approx 2.4$ ms. This work was
motivated by the design considerations and expected the performance of an
adaptive optics system that is currently being planned for the telescope.

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The categories of this paper are: nlin
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int