Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Field-dependent surface resistance of a superconducting RF cavity caused
  by surface impurity   Q-slope issue, which is caused by the field dependent surface resistance,
puzzled people for a long time in SRF fields. In this paper, we related the
Q-slope with surface treatments; and proposed a surface-impurity model to
explain the field-dependent of surface resistance of SRF cavities. Eighteen
cavity-test results have been analyzed to examine the model. These cavities
were treated by different recipes: Nitrogen-doping; BCP and HF-rinsing; EP with
120{\deg}C baking; and EP without 120{\deg}C baking. The performance of these
cavities, which is normally represented by cavity quality factor versus
accelerating gradient or surface magnetic field curves (Q0 vs. Eacc or Q0 vs.
B), has included all types of Q-slope, such as Low-field Q-slope, Medium-field
Q-slope, and Anti-Q-slope. The data fittings are quite successful; the fitting
results will be shown. The model can be used to evaluate the effectiveness of
the surface treatments. At last, the paper discussed the way to build a high-Q
high-gradient SRF cavity.

18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph