Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Central Production of $\eta$ via Double Pomeron Exchange and Double
  Reggeon Exchange in the Sakai-Sugimoto Model   We use holographic QCD to study Pomeron- and Reggeon-mediated central
production in Regge regime hadronic scattering. We focus specifically on $\eta$
production in proton-proton collisions. While previous work studied the
Pomeron-mediated process, the mesonic Regge trajectories ("Reggeons") we now
incorporate contribute significantly at experimentally probed energies. We use
the five-point open string amplitude (in flat space) to construct approximate
propagators for the Reggeon states, and the five-point closed string amplitude
for the Pomeron. Using these "holographic" Reggeons and Pomerons, and
low-energy couplings derived in the Sakai-Sugimoto model, we compute the
differential and total cross sections at $\sqrt{s}$ =29.1 GeV. Our calculation
of the total cross section is $\sigma =236 \ \mathrm{nb}$, while the
experimentally measured value is $\sigma = 3859 \ \mathrm{nb}$. The discrepancy
between our result and the measured value may indicate that our model
systematically underestimates the values of the relevant coupling constants.

16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th