Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral functions from Hadronic Tau Decays and QCD   Hadronic decays of the $\tau$ lepton provide a clean environment to study
hadron dynamics in an energy regime dominated by resonances, with the
interesting information captured in the spectral functions. Recent results from
ALEPH on exclusive channels are presented, with some emphasis on the $\pi \piz$
final state which plays a crucial role for the determination of the hadronic
contribution to the muon anomalous magnetic moment. Inclusive spectral
functions are the basis for QCD analyses, delivering an accurate determination
of the strong coupling constant, quantitative information on nonperturbative
contributions and a measurement of the mass of the strange quark.

27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga