Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The First Scientific Results from the Pierre Auger Observatory   The southern site of the Pierre Auger Observatory is under the construction
near Malargue in Argentina and now more than 60% of the detectors are
completed. The observatory has been collecting data for over 1 year and the
cumulative exposure is already similar to that of the largest forerunner
experiments. The hybrid technique provides model-independent energy
measurements from the Fluorescence Detector to calibrate the Surface Detector.
Based on this technique, the first estimation of the energy spectrum above 3
EeV has been presented and is discussed in this paper.

37
The categories of this paper are: supr-con
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat