Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Molecular dynamics simulation of threshold displacement energy and
  primary damage state in Niobium   In this work, a many-body potential of Nb for radiation damage simulation was
developed based on EAM, and most of the point defects of Nb can be predicted
properly by this potential. By using the constructed potential, the
direction-specific threshold displacement energies (TDE) and displacement
cascades up to 20 keV of Nb were performed through molecular dynamics
simulations. The calculated results of TDE are in good agreement with previous
work for V, Mo and experimental measurements. Lowest TDE was found in <100>
direction, and local minas of TDE were found in three low-index directions,
which has relation: Ed[100]<Ed[111]<Ed[110]. The evolution of displacement
cascades, number of the created point defects, the cascade efficiency the
clustering of point defects, and temperature role of these parameters at
different PKA energies were systematic investigated. It is found that the
cascade efficiency is low and it is can be fitted by a power function as many
published work did. The fraction of clustered point defects obtained in this
work is low, and only some small clusters were formed at the end of thermal
spike. As the temperature increases, the productions of point defects and
cascade efficiency were somewhat decreases, however, the fraction of clustered
point defects decreases more obvious.

10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc