Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Composition of Transiting and Transiting-only super-Earths   The relatively recent detections of the first three transiting super-Earths
mark the beginning of a subfield within exoplanets that is both fruitful and
challenging. The first step into characterizing these objects is to infer their
composition given the degenerate character of the problem. The calculations
show that Kepler-10b has a composition between an Earth-like and a Mercury-like
(enriched in iron) composition. In contrast, GJ 1214b is too large to be solid,
and has to have a volatile envelope. Lastly, while three of the four reported
mass estimates of CoRoT-7b allow for a rocky composition, one forbids it and
can only be reconciled with significant amounts of water vapor. In addition to
these three transiting low-mass planets, there are now more than one thousand
Kepler planets with only measured radius. Even without a mass measurement
("transiting-only") it is still possible to place constraints on the amount of
volatile content of the highly-irradiated planets, as their envelopes, if
present, are flared. Using Kepler-9d as an example, we estimate its water
vapor, or hydrogen and helium content to be less than 50% or 0.1% by mass
respectively.

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The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex