Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of Chemically Enriched QSO Absorbers near z ~ 2.3 Galaxies:
  Galaxy-Formation Feedback Signatures in the IGM   We present a study of galaxies and intergalactic gas toward the z=2.73 quasar
HS1700+6416, to explore the effects of galaxy formation feedback on the IGM.
Our observations and ionization simulations indicate that the volume within
100-200 h_71^{-1} physical kpc of high-redshift galaxies contains very small,
dense, and metal-rich absorption-line regions. These systems often contain
shock-heated gas seen in OVI, and may exhibit [Si/C] abundance enhancements
suggestive of Type II supernova enrichment. We argue that the absorbers
resemble thin sheets or bubbles, whose physical properties can be explained
with a simple model of radiatively efficient shocks propegating through the
IGM. Their high metallicities suggest that these shocks are being expelled
from--rather than falling into--star forming galaxies. There is a dropoff in
the IGM gas density at galaxy impact parameters beyond ~300 physical kpc that
may trace boundaries of gas structures where the galaxies reside. The local
heavy-element enhancement covers 100-200 kpc; beyond this the observed
abundances blend into the general IGM. Supernova-driven winds or dynamical
stripping of interstellar gas appears to affect the IGM near massive galaxies,
even at R>~100 kpc. However, these feedback systems represent only a few
percent of the Lya forest mass at z~2.5. Their mass could be larger if the more
numerous metal-poor CIV systems at >~200 kpc are tepid remnants of very
powerful winds. Based on present observations it is not clear that this
scenario is to be favored over one involving pre-enrichment by smaller galaxies
at z>~6.

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The categories of this paper are: chem-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: physics
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph
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The categories of this paper are: math
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The categories of this paper are: quant-ph