Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simultaneous quantitative imaging of surface and magnetic forces   We demonstrate quantitative force imaging of long-range magnetic forces
simultaneously with near-surface van-der-Waals and contact-mechanics forces
using intermodulation atomic force microscopy. Magnetic forces at the 200 pN
level are separated from near-surface forces at the 30 nN level. Imaging of
these forces is performed in both the contact and non-contact regimes of
near-surface interactions.

16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int