Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A first measurement of the interaction cross section of the tau neutrino   The DONuT experiment collected data in 1997 and published first results in
2000 based on four observed $\nu_\tau$ charged-current (CC) interactions. The
final analysis of the data collected in the experiment is presented in this
paper, based on $3.6 \times 10^{17}$ protons on target using the 800 GeV
Tevatron beam at Fermilab. The number of observed $\nu_\tau$ CC interactions is
9, from a total of 578 observed neutrino interactions. We calculated the
energy-independent part of the tau-neutrino CC cross section ($\nu + \bar
\nu$), relative to the well-known $\nu_e$ and $\nu_\mu$ cross sections. The
ratio $\sigma(\nu_\tau)$/$\sigma(\nu_{e,\mu})$ was found to be
$1.37\pm0.35\pm0.77$. The $\nu_\tau$ CC cross section was found to be $0.72 \pm
0.24\pm0.36 \times 10^{-38}$ cm$^{2}\rm{GeV}^{-1}$. Both results are in
agreement the Standard Model.

37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
2
The categories of this paper are: math