Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurements of the Top-quark Mass and the ttbar Cross Section in the
  Hadronic tau + Jets Decay Channel at sqrt(s) = 1.96 TeV   We present the first direct measurement of the top-quark mass using $\ttbar$
events decaying in the hadronic $\tau$ + jets decay channel. Using data
corresponding to an integrated luminosity of 2.2 fb$^{-1}$ collected by the CDF
II detector in $p\bar{p}$ collisions at $\sqrt{s}=1.96 ~TeV$ at the Fermilab
Tevatron, we measure the $t\bar{t}$ cross section, $\sigma_{t\bar{t}}$, and the
top-quark mass, M$_{top}$. We extract M$_{top}$ from a likelihood based on
per-event probabilities calculated with leading-order signal and background
matrix elements. We measure $\sigma_{t\bar{t}} = 8.8 \pm 3.3 ~(\mathrm{stat})
\pm 2.2 ~(\mathrm{syst}) ~\mathrm{pb}$ and M$_{top} = 172.7 \pm 9.3
~(\mathrm{stat}) \pm 3.7 ~(\mathrm{syst}) ~GeV/c^2$.

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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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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: stat
10
The categories of this paper are: q-bio
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: physics
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The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
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The categories of this paper are: q-fin