Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Empirical Tests of Pre-Main-Sequence Stellar Evolution Models with
  Eclipsing Binaries   We examine the performance of standard PMS stellar evolution models against
the accurately measured properties of a benchmark sample of 26 PMS stars in 13
EB systems. We provide a definitive compilation of all fundamental properties
for the EBs. We also provide a definitive compilation of the various PMS model
sets. In the H-R diagram, the masses inferred for the individual stars by the
models are accurate to better than 10% above 1 Msun, but below 1 Msun they are
discrepant by 50-100%. We find evidence that the failure of the models to match
the data is linked to the triples in the EB sample; at least half of the EBs
possess tertiary companions. Excluding the triples, the models reproduce the
stellar masses to better than ~10% in the H-R diagram, down to 0.5 Msun, below
which the current sample is fully contaminated by tertiaries. We consider
several mechanisms by which a tertiary might cause changes in the EB properties
and thus corrupt the agreement with stellar model predictions. We show that the
energies of the tertiary orbits are comparable to that needed to potentially
explain the scatter in the EB properties through injection of heat, perhaps
involving tidal interaction. It seems from the evidence at hand that this
mechanism, however it operates in detail, has more influence on the surface
properties of the stars than on their internal structure, as the lithium
abundances are broadly in good agreement with model predictions. The EBs that
are members of young clusters appear individually coeval to within 20%, but
collectively show an apparent age spread of ~50%, suggesting true age spreads
in young clusters. However, this apparent spread in the EB ages may also be the
result of scatter in the EB properties induced by tertiaries. [Abridged]

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The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph