Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photo Reactions on the Deuteron in the Delta-Resonance   Photo disintegration of the deuteron and photo pionproduction on the deuteron
are described in the region of the $\Delta$-resonance. The two reactions are
unitarily coupled. A novel definition of electromagnetic exchange currents in
the presence of pionproduction is given. Numerical predictions are done for
spin-independent and spin-dependent observables of both reactions. The
sensitivity of the results with respect to the nucleon-$\Delta$ transition
current and with respect to the irreducible nucleon-$\Delta$ potential is
studied.

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The categories of this paper are: adap-org
2
The categories of this paper are: math
3
The categories of this paper are: physics
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th