Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two Disk Components from a Gas Rich Disk-Disk Merger   We employ N-body, smoothed particle hydrodynamical simulations, including
detailed treatment of chemical enrichment, to follow a gas-rich merger which
results in a galaxy with disk morphology. We trace the kinematic, structural
and chemical properties of stars formed before, during, and after the merger.
We show that such a merger produces two exponential disk components, with the
older, hotter component having a scale-length 20% larger than the
later-forming, cold disk. Rapid star formation during the merger quickly
enriches the protogalactic gas reservoir, resulting in high metallicities of
the forming stars. These stars form from gas largely polluted by Type II
supernovae, which form rapidly in the merger-induced starburst. After the
merger, a thin disk forms from gas which has had time to be polluted by Type Ia
supernovae. Abundance trends are plotted, and we examine the proposal that
increased star formation during gas-rich mergers may explain the high
alpha-to-iron abundance ratios which exist in the relatively high-metallicity
thick disk component of the Milky Way.

17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga