Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nodal Gap in Fe-Based Layered Superconductor LaO_0.9F_{0.1-delta}FeAs
  Probed by Specific Heat Measurements   We report the specific heat measurements on the newly discovered Fe-based
layered superconductor LaO_0.9F_{0.1-delta}FeAs with the onset transition
temperature T_c \approx 28 K. A nonlinear magnetic field dependence of the
electronic specific heat coefficient gamma(H) has been found in the low
temperature limit, which is consistent with the prediction for a nodal
superconductor. The maximum gap value Delta_0 \approx 3.4$\pm$0.5 meV was
derived by analyzing gamma(H) based on the d-wave model. We also detected the
electronic specific heat difference between 9 T and 0 T in wide temperature
region, a specific heat anomaly can be clearly observed near T_c. The Debye
temperature of our sample was determined to be about 315.7 K. Our results
suggest an unconventional mechanism for this new superconductor.

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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn