Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: e+ e- pairs from pi- A reactions   We calculate dilepton production for the reactions $\pi^-$C and $\pi^-$Pb at
1.3 GeV within a semi-classical BUU transport model and compare our results to
a previously published calculation. We show that a modified treatment of the
$\rho$-meson production and propagation gives substantially different results.
We, furthermore, discuss uncertainties related to the electromagnetic decay of
the $\rho$-meson and the elementary $\pi^- N \to e^+ e^- X$ channels.

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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
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The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-fin