Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental Persistence Probability for Fluctuating Steps   The persistence behavior for fluctuating steps on the $Si(111)$ $(\sqrt3
\times \sqrt3)R30^{0} - Al$ surface was determined by analyzing time-dependent
STM images for temperatures between 770 and 970K. The measured persistence
probability follows a power law decay with an exponent of $\theta=0.77 \pm
0.03$. This is consistent with the value of $\theta= 3/4$ predicted for
attachment/detachment limited step kinetics. If the persistence analysis is
carried out in terms of return to a fixed reference position, the measured
persistence probability decays exponentially. Numerical studies of the Langevin
equation used to model step motion corroborate the experimental observations.

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The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th