Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Energy determination in the Akeno Giant Air Shower Array experiment   Using data from more than ten-years of observations with the Akeno Giant Air
Shower Array (AGASA), we published a result that the energy spectrum of
ultra-high energy cosmic rays extends beyond the cutoff energy predicted by
Greisen, and Zatsepin and Kuzmin. In this paper, we reevaluate the energy
determination method used for AGASA events with respect to the lateral
distribution of shower particles, their attenuation with zenith angle, shower
front structure, delayed particles observed far from the core and other
factors. The currently assigned energies of AGASA events have an accuracy of
$\pm$25% in event-reconstruction resolution and $\pm$18% in systematic errors
around 10$^{20}$eV. This systematic uncertainty is independent of primary
energy above 10$^{19}$eV. Based on the energy spectrum from 10$^{14.5}$eV to a
few times 10$^{20}$eV determined at Akeno, there are surely events above
10$^{20}$eV and the energy spectrum extends up to a few times 10$^{20}$eV
without a GZK-cutoff.

36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics