Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A deep look into the core of young clusters. II. lambda-Orionis   Over the past years, the lambda-Orionis cluster has been a prime location for
the study of young very low mass stars, substellar and isolated planetary mass
objects and the determination of the initial mass function and other properties
of low mass cluster members. In the continuity of our previous studies of young
associations cores, we search for ultracool members and new multiple systems
within the central 5.3' (~0.6pc) of the cluster. We obtained deep seeing
limited J, Ks-band images of the 5.3' central part of the cluster with NTT/SofI
and H-band images with CAHA/Omega2000. These images were complemented by
multi-conjugate adaptive optics (MCAO) H and Ks images of the 1.5' central
region of the lambda-Orionis cluster obtained with the prototype MCAO facility
MAD at the VLT. The direct vicinity of the massive lambda-Ori O8III-star was
probed using NACO/SDI at the VLT. Finally, we also retrieved Spitzer IRAC
images of the same area and used archival Subaru Suprime-Cam and CFHT CFHT12K
i-band images. We report the detection of 9 new member candidates selected from
optical and near-IR color-color and color-magnitude diagrams and 7 previously
known members. The high spatial resolution images resolve 3 new visual multiple
systems. Two of them are most likely not members of the association. The third
one is made of a brown dwarf candidate companion to the F8V star HD36861C. The
simultaneous differential images allow us to rule out the presence of visual
companions more massive than M>0.07Msun in the range 1-2.5", and M>0.25Msun in
the range 0.5-2.5"

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The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
2
The categories of this paper are: math
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph
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The categories of this paper are: math-ph