Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polarization and Handedness in Tau -> 3 Pi + Neutrino Decay Produced in
  e+e- Annihilations   We discuss the concept of handedness applied to $\tau$ production in $e^+e^-$
annihilations with $\tau$ decaying into $a_1\nu_\tau \to 3\pi\nu_\tau$. The
$a_1\to 3\pi$ decay is particularly interesting since it (together with $h_1\to
3\pi$) is the lightest hadronic decay in which the helicity of the initial
state can be determined from the distribution of the final particle momenta.
Thus it is the first example of a helicity self-analysing strong decay, as
$\Lambda\to N\pi$ is for weak decays. Apart from providing a new method for
determining the $\tau$ polarization from the parity conserving part in the weak
decay, this reaction provides a very instructive and useful demonstration of
the handedness asymmetry as a measure of parton polarization. Thus we believe
that experience gained from analyses of handedness in $\tau\to 3\pi\nu_\tau$
decay will be very useful when looking for the similar asymmetry of jet
handedness which can measure quark or gluon polarization.

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The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
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The categories of this paper are: adap-org