Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Absence of Hybridization Gap in Heavy Electron Systems and Analysis of
  YbAl3 in terms of Nearly Free Electron Conduction Band   In the analysis of the heavy electron systems, theoretical models with c-f
hybridization gap are often used. We point out that such a gap does not exist
and the simple picture with the hybridization gap is misleading in the metallic
systems, and present a correct picture by explicitly constructing an effective
band model of YbAl_3. Hamiltonian consists of a nearly free electron model for
conduction bands which hybridize with localized f-electrons, and includes only
a few parameters. Density of states, Sommerfeld coefficient, f-electron number
and optical conductivity are calculated and compared with the band calculations
and the experiments.

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The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph