Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chemical similarities between Galactic bulge and local thick disk red
  giants: O, Na, Mg, Al, Si, Ca and Ti   ... We confirm the well-established differences for [$\alpha$/Fe] at a given
metallicity between the local thin and thick disks. For all the elements
investigated, we find no chemical distinction between the bulge and the local
thick disk, in agreement with our previous study of C, N and O but in contrast
to other groups relying on literature values for nearby disk dwarf stars. For
-1.5 < [Fe/H] < -0.3 exactly the same trend is followed by both the bulge and
thick disk stars, with a star-to-star scatter of only 0.03 dex. Furthermore,
both populations share the location of the knee in the [alpha/Fe] vs [Fe/H]
diagram. It still remains to be confirmed that the local thick disk extends to
super-solar metallicities as is the case for the bulge. These are the most
stringent constraints to date on the chemical similarity of these stellar
populations. Our findings suggest that the bulge and local thick disk stars
experienced similar formation timescales, star formation rates and initial mass
functions, confirming thus the main outcomes of our previous homogeneous
analysis of [O/Fe] from infrared spectra for nearly the same sample. The
identical alpha-enhancements of thick disk and bulge stars may reflect a rapid
chemical evolution taking place before the bulge and thick disk structures we
see today were formed, or it may reflect Galactic orbital migration of inner
disk/bulge stars resulting in stars in the solar neighborhood with thick-disk
kinematics.

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The categories of this paper are: physics
28
The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
18
The categories of this paper are: econ
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The categories of this paper are: nlin
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: bayes-an