Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: In-situ measurement of the permittivity of helium using microwave NbN
  resonators   By measuring the electrical transport properties of superconducting NbN
quarter-wave resonators in direct contact with a helium bath, we have
demonstrated a high-speed and spatially sensitive sensor for the permittivity
of helium. In our implementation a $\sim10^{-3}$ mm$^3$ sensing volume is
measured with a bandwidth of 300 kHz in the temperature range 1.8 to 8.8 K. The
minimum detectable change of the permittivity of helium is calculated to be
$\sim6\times$$10^{-11}$ $\epsilon_0$/Hz$^{1/2}$ with a sensitivity of order
$10^{-13}$ $\epsilon_0$/Hz$^{1/2}$ easily achievable. Potential applications
include operation as a fast, localized helium thermometer and as a transducer
in superfluid hydrodynamic experiments.

3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom