Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pulsed field studies of the magnetization reversal in molecular
  nanomagnets   We report experimental studies of crystals of Mn12 molecular magnetic
clusters in pulsed magnetic fields with sweep rates up to 4x10^3 T/s. The steps
in the magnetization curve are observed at fields that are shifted with respect
to the resonant field values. The shift systematically increases as the rate of
the field sweep goes up. These data are consistent with the theory of the
collective dipolar relaxation in molecular magnets.

28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas