Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Disappearance of the Spin Gap in a Zn doped 2-Leg Ladder Compound
  Sr(Cu1-xZnx)2O3   An inelastic neutron scattering study was performed on a Zn-substituted
spin-1/2 Heisenberg 2-leg ladder compound Sr(Cu1-xZnx)2O3 (x < 0.04) to
investigate nonmagnetic impurity effects on the quantum spin system with a
large spin gap of about 400 K. The magnitude of the spin gap was found to be
independent of Zn concentration, 33 meV, while the integrated magnetic
scattering which corresponds to the singlet-triplet excitation decreased
monotonically with increasing x. On account of the total-sum rule, this result
supports the existence of a finite in-gap density of states at E = 0 which was
suggested from the T-linear magnetic specific heat.

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The categories of this paper are: funct-an
1
The categories of this paper are: cs
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc