Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatially resolved eastward winds and rotation of HD 189733b   We measure wind velocities on opposite sides of the hot Jupiter HD$\,$189733b
by modeling sodium absorption in high-resolution HARPS transmission spectra.
Our model implicitly accounts for the Rossiter-McLaughlin effect, which we show
can explain the high wind velocities suggested by previous studies. Our results
reveal a strong eastward motion of the atmosphere of HD$\,$189733b, with a
redshift of $2.3^{+1.3}_{-1.5}$$\,$km$\,$s$^{-1}$ on the leading limb of the
planet and a blueshift of $5.3^{+1.0}_{-1.4}$$\,$km$\,$s$^{-1}$ on the trailing
limb. These velocities can be understood as a combination of tidally locked
planetary rotation and an eastward equatorial jet; closely matching the
predictions of atmospheric circulation models. Our results show that the sodium
absorption of HD$\,$189733b is intrinsically velocity broadened and so previous
studies of the average transmission spectrum are likely to have overestimated
the role of pressure and thermal broadening.

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The categories of this paper are: math
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The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg