Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Aging effect in Magnetotransport Property of Oxygen adsorbed BaFe2As2   Presence of Oxygen (O2) has been found by Energy Dispersive X-ray Analysis
(EDAX) on the surfaces of flux grown BaFe2As2 single crystals which were kept
in air ambience for several months. Transport studies show that the O2 adsorbed
crystals are more resistive and do not display any sharp slope change near 140
K which is the well known Spin Density Wave (SDW) transition temperature (TSDW)
accompanying structural transition for as grown BaFe2As2. An anomalous slope
change in resistivity is observed around 18 K at 0 and 5T. Magnetoresistance
(MR) is noticed to increase as a function of applied field (H) quite
differently than that for as grown crystals below TSDW which may be attributed
to aging effec

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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: stat
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
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The categories of this paper are: comp-gas
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol