Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GRB 050826: A Subluminous Event at z = 0.296 Finds its Place in the
  Luminosity Distribution of Gamma-Ray Burst Afterglows   We present the optical identification and spectroscopy of the host galaxy of
GRB 050826 at a redshift z = 0.296 +/- 0.001. Image subtraction among
observations obtained on three consecutive nights, reveals a fading object 5
hours after the burst, confirming its identification as the optical afterglow
of this event. Deep imaging shows that the optical afterglow is offset by 0.4
arcseconds (~1.76 kpc) from the center of its irregular host galaxy, which is
typical for long-duration gamma-ray bursts. Combining these results with X-ray
measurements acquired by the Swift XRT instrument, we find that GRB 050826
falls entirely within the subluminous, subenergetic group of long gamma-ray
bursts at low redshift (z < 0.3). The results are discussed in the context of
models that possibly account for this trend, including the nature of the
central engine, the evolution of progenitor properties as a function of
redshift, and incompleteness in current gamma-ray burst samples.

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The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: cs
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The categories of this paper are: atom-ph
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: physics
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The categories of this paper are: econ
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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph