Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Affinity, stoichiometry and cooperativity of heterochromatin protein 1
  (HP1) binding to nucleosomal arrays
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess