Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nuclear quadrupole resonances in compact vapor cells: the crossover from
  the NMR to the NQR interaction regimes   We present the first experimental study that maps the transformation of
nuclear quadrupole resonances from the pure nuclear quadrupole regime to the
quadrupole-perturbed Zeeman regime. The transformation presents an interesting
quantum-mechanical problem, since the quantization axis changes from being
aligned along the axis of the electric-field gradient tensor to being aligned
along the magnetic field. We achieve large nuclear quadrupole shifts for I =
3/2 131-Xe by using a 1 mm^3 cubic cell with walls of different materials. When
the magnetic and quadrupolar interactions are of comparable size, perturbation
theory is not suitable for calculating the transition energies. Rather than use
perturbation theory, we compare our data to theoretical calculations using a
Liouvillian approach and find excellent agreement.

11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
3
The categories of this paper are: physics
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess