Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Momentum dependence of pion-induced $\phi$ meson production on nuclei
  near threshold   We study the near-threshold pion-induced production of $\phi$ mesons off
nuclei in the kinematical conditions of the HADES experiment, recently
performed at GSI. The calculations have been performed within a collision model
based on the nuclear spectral function. The model accounts for both the primary
$\pi^-$ meson--proton ${\pi^-}p \to {\phi}n$ and the secondary pion--nucleon
${\pi}N \to {\phi}N$ $\phi$ production processes as well as the effects of the
nuclear $\phi$ and nucleon mean-field potentials. We find that the primary
reaction channel ${\pi^-}p \to {\phi}n$ dominates in the $\phi$ production off
$^{12}$C and $^{184}$W target nuclei in the HADES acceptance window at incident
pion momentum of 1.7 GeV/c. We calculate the momentum dependence of the
absolute and relative (transparency ratio) $\phi$ meson yields from the above
direct channel. The calculations have been performed for this initial pion
momentum allowing for different options for the ${\phi}N$ absorption cross
section $\sigma_{{\phi}N}$ and different scenarios for the in-medium mass
shifts of the $\phi$ meson and secondary neutron, produced together with $\phi$
in this channel. We demonstrate that the transparency ratio for the $\phi$
mesons has, contrary to the absolute cross sections, an insignificant
sensitivity to the $\phi$ meson and secondary neutron in-medium mass shifts at
$\phi$ momenta studied in the HADES experiment. On the other hand, we show that
there are measurable changes in the transparency ratio due to the ${\phi}N$
absorption cross section, which means that such relative observable can be
useful to help determine this cross section from the data taken in the HADES
experiment.

19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th