Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Bimodal Colors of Centaurs and Small Kuiper Belt Objects   Ever since the very first photometric studies of Centaurs and Kuiper Belt
Objects (KBOs) their visible color distribution has been controversial. That
controversy gave rise to a prolific debate on the origin of the surface colors
of these distant icy objects of the Solar System. Two different views attempt
to interpret and explain the large variability of colors, hence surface
composition. Are the colors mainly primordial and directly related to the
formation region, or are they the result of surface evolution processes? To
date, no mechanism has been found that successfully explains why Centaurs,
which are escapees from the Kuiper Belt, exhibit two distinct color groups,
whereas KBOs do not. In this letter, we readdress this issue using a carefully
compiled set of B-R colors and H({\alpha}) magnitudes (as proxy for size) for
253 objects, including data for 10 new small objects.
  We find that the bimodal behavior seen among Centaurs is a size related
phenomenon, common to both Centaurs and small KBOs, i.e. independent of
dynamical classification. Further, we find that large KBOs also exhibit a
bimodal behavior of surface colors, albeit distinct from the small objects and
strongly dependent on the `Haumea collisional family' objects. When plotted in
B-R, H({\alpha}) space, the colors of Centaurs and KBOs display a peculiar N
shape.

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The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: plasm-ph
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The categories of this paper are: econ
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The categories of this paper are: cs
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys