Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Highest Energy Proton-Nucleus Cross Sections   The description of very high energy proton-proton cross sections in terms of
a `black disc' with an `edge' allows of a simple generalization to highest
energy proton-nucleus cross sections. This results in a leading $ln^2W$ term
and a $ln\, W$ term whose coefficient depends linearly on the radius of the
nucleus ($W$ the c.m. energy). The necessary parameters are determined from the
fits to p-p data. Since the coefficient of the $ln W$ term is rather large, it
is doubtful that the regime of $ln^2W$ dominance can be reached with available
energies in accelerators or cosmic rays. However, the $ln W$ term can be
relevant for highest energy cosmic rays in the atmosphere, where a large
increase for the cross section on nitrogen is expected. Tests of the theory
should be possible by studying the coefficient of $ln W$ at p-nucleus
colliders.

22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph