Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NMR Studies on the Superconducting Symmetry of Iron Pnictide Systems   NMR longitudinal relaxation rates 1/T1 and Knight shifts K have been measured
for superconducting samples of LaFe1-yCoyAsO1-xFx with y=0.0 and 0.0075 and for
a nonsuperconducting metallic sample with y=0.1, where the x values are always
fixed at 0.11. The temperature (T) dependence the relaxation rates 1/T1 of the
superconducting samples has been found to be markedly different from the
behavior 1/T1 T^(2.5-3.0) reported by many groups in the entire T range
measured (from the temperature immediately below the superconducting transition
temperature Tc down to (0.1-0.2)Tc). The nonexistence of the coherence peak has
also been found. Based on the results of the measurements and other kinds of
existing data, arguments are presented on the superconducting symmetry of the
Fe pnictide systems, where the several points which cannot be easily understood
by existing theories, are pointed out. Results of the measurements on the
nonsuperconducting metallic samples are also presented.

3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th