Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Gain and noise spectral density in an electronic parametric amplifier
  with added white noise
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg