Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Post-Linac Collimation System for the European XFEL   In this article we give an overview of the the post-linac collimation system
for the European X-Ray Free-Electron Laser (XFEL) Facility with main emphasis
on lattice and optics design.

21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ