Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Antiproton production in Ni+Ni collisions at 1.85 GeV/nucleon   Antiproton production in Ni+Ni collisions at 1.85 GeV/nucleon is studied in
the relativistic Vlasov-Uehling-Uhlenbeck model. The self-energies of the
antiproton are determined from the nucleon self-energies by the G-parity
transformation. Also, the final-state interactions of the antiproton including
both rescattering and annihilation are explicitly treated. With a soft nuclear
equation of state, the calculated antiproton momentum spectrum is in good
agreement with recent experimental data from the heavy-ion synchrotron at GSI.
The effect due to the reduced nucleon and antinucleon masses in a medium is
found to be more appreciable than in earlier Bevalac experiments with lighter
systems and at higher energies.

29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga