Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The isolation of Luminous Blue Variables resembles aging B-type
  supergiants, not the most massive unevolved stars   Luminous blue variables (LBVs) are suprisingly isolated from the massive
O-type stars that are their putative progenitors in single-star evolution,
implicating LBVs as binary evolution products. Aadland et al. (A19) found that
LBVs are, however, only marginally more dispersed than a photometrically
selected sample of bright blue stars (BBS) in the LMC, leading them to suggest
that LBV environments may not exclude a single-star origin. In both
comparisons, LBVs have the same median separation, confirming that any
incompleteness in the O-star sample does not fabricate LBV isolation. Instead,
the relative difference arises because the photometric BBS sample is far more
dispersed than known O-type stars. Evidence suggests that the large BBS
separation arises because it traces less massive (~20 Msun), aging blue
supergiants. Although photometric criteria used by A19 aimed to select only the
most massive unevolved stars, visual-wavelength color selection cannot avoid
contamination because O and early B stars have almost the same intrinsic color.
Spectral types confirm that the BBS sample contains many B supergiants.
Moreover, the observed BBS separation distribution matches that of
spectroscopically confirmed early B supergiants, not O-type stars, and matches
predictions for a ~10 Myr population, not a 3-4 Myr population. A broader
implication for ages of stellar populations is that bright blue stars are not a
good tracer of the youngest massive O-type stars. Bright blue stars in nearby
galaxies (and unresolved blue light in distant galaxies) generally trace
evolved blue supergiants akin to SN 1987A's progenitor.

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The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
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The categories of this paper are: q-alg