Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constraints on Spin-Dependent Short-Range Interaction between Nucleons   We report on the search for a new spin-dependent P- and T-violating
interaction between nucleons mediated by light, pseudoscalar bosons such as the
axion which was invented to solve the strong CP problem. Our experimental
approach is to use an ultra-sensitive low-field magnetometer based on the
detection of free precession of co-located 3He and 129Xe nuclear spins using
SQUIDs as low-noise magnetic flux detectors. In the presence of an unpolarized
mass the precession frequency shif

21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
30
The categories of this paper are: q-alg