Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 17 new very low-mass members in Taurus. The brown dwarf deficit
  revisited   Recent studies of the substellar population in the Taurus cloud have revealed
a deficit of brown dwarfs (BD) compared to the Trapezium cluster population
(Briceno et al 1998; Luhman 2000; Luhman et al 2003a; Luhman 2004). However,
these works have concentrated on the highest stellar density regions of the
Taurus cloud. We have performed a large scale optical survey of this region,
covering a total area of 30 deg^2, and encompassing the densest part of the
cloud as well as their surroundings, down to a mass detection limits of 15
Jupiter Masses (MJ). In this paper, we present the optical spectroscopic
follow-up observations of 97 photometrically selected potential new low-mass
Taurus members, of which 27 are strong late-M (SpT < M4V) candidates. These
observations reveal 5 new very low mass (VLM) Taurus members and 12 new BDs.
Combining our observations with previously published results, we derive an
updated substellar to stellar ratio in Taurus of Rss =0.23 +/- 0.05. This ratio
now appears consistent with the value previously derived in the Trapezium
cluster under similar assumptions of 0.26 +/- 0.04. We find strong indication
that the relative numbers of BDs with respect to stars is decreased by a factor
2 in the central regions of the aggregates with respect to the more distributed
population. Our findings are best explained in the context of the
embryo-ejection model where brown dwarfs originate from dynamical interactions
in small N unstable multiple systems.

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The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an
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The categories of this paper are: chem-ph
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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: nucl-th
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci