Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Galaxy Clusters in Formation: Determining the Age of the Red-Sequence in
  Optical and X-ray Clusters at z~1 with HST
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ