Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Emission of neutron-proton and proton-proton pairs in neutrino
  scattering   We use a recently developed model of relativistic meson-exchange currents to
compute the neutron-proton and proton-proton yields in $(\nu_\mu,\mu^-)$
scattering from $^{12}$C in the 2p-2h channel. We compute the response
functions and cross sections with the relativistic Fermi gas model for
different kinematics from intermediate to high momentum transfers. We find a
large contribution of neutron-proton configurations in the initial state, as
compared to proton-proton pairs. In the case of charge-changing neutrino
scattering the 2p-2h cross section of proton-proton emission ({\it i.e.,} np in
the initial state) is much larger than for neutron-proton emission ({\it i.e.,}
two neutrons in the initial state) by a $(\omega,q)$-dependent factor. The
different emission probabilities of distinct species of nucleon pairs are
produced in our model only by meson-exchange currents, mainly by the $\Delta$
isobar current. We also analyze other effects including exchange contributions
and the effect of the axial and vector currents.

26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
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The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int