Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Large Transport Critical Current Densities of Ag Sheathed
  (Ba,K)Fe2As2+Ag Superconducting Wires Fabricated by an ex-situ Powder-in-Tube
  (PIT) Process   We report large transport critical current densities observed in Ag-added
(Ba,K)Fe2As2 superconducting wires prepared by an ex-situ powder-in-tube (PIT)
process. The wire has a simple composite structure sheathed only by Ag. A
precursor bulk material prepared by a melting process was ground into powder
and put into a Ag tube. The composite was then cold worked into a wire and heat
treated at 850$^\circ$C for sintering. Transport critical current densities,
Jc, at 4.2 K are 1.0\times104 A/cm2 (Ic = 60.7 A) in self field and
1.1\times103 A/cm2 (Ic = 6.6 A) in 10 T. These are the highest values reported
so far for the Fe-based superconducting wires.

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The categories of this paper are: acc-phys
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: math
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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: astro-ph
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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol