Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A New Cryogenic Apparatus to Search for the Neutron Electric Dipole
  Moment   A cryogenic apparatus is described that enables a new experiment, nEDM@SNS,
with a major improvement in sensitivity compared to the existing limit in the
search for a neutron Electric Dipole Moment (EDM). It uses superfluid $^4$He to
produce a high density of Ultra-Cold Neutrons (UCN) which are contained in a
suitably coated pair of measurement cells. The experiment, to be operated at
the Spallation Neutron Source at Oak Ridge National Laboratory, uses polarized
$^3$He from an Atomic Beam Source injected into the superfluid $^4$He and
transported to the measurement cells as a co-magnetometer. The superfluid
$^4$He is also used as an insulating medium allowing significantly higher
electric fields, compared to previous experiments, to be maintained across the
measurement cells. These features provide an ultimate statistical uncertainty
for the EDM of $2-3\times 10^{-28}$ e-cm, with anticipated systematic
uncertainties below this level.

8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ