arXiv subjects

Xiao-Ting Xu

Publications and source records attributed to Xiao-Ting Xu.

3 recordsLinked to original sources

arXiv2026

Effect of super-Gaussian pulse shape on pair production in chirped electric field with spatial inhomogeneity

Pair production in spatially inhomogeneous chirped electric fields with super-Gaussian pulse shape is investigated using the Dirac-Heisenberg-Wigner formalism, and the effect of super-Gaussian pulse shapes on the reduced momentum spectrum and the reduced total yield of created particles is mainly concerned. It is found that with the variation of the super-Gaussian envelope exponent, the momentum spectrum exhibits the more pronounced oscillations, shifting and broadening. The total yield of created particles increases monotonically with the increase of the super-Gaussian envelope exponent in the high-frequency fields with small chirp and low-frequency fields with any chirp. Meanwhile, the total yield of created particles under the super-Gaussian pulse electric fields is approximately twice that produced with the usual Gaussian pulse envelope. These results can provide theoretical guidance for optimizing the form of external field to enhance the vacuum pair production rate.

hep-ph↗

arXiv2026

Electron-positron pair production in spatially inhomogeneous electric fields with quadratically symmetric chirp

Electron-positron pair production from vacuum in spatially inhomogeneous electric fields with quadratically symmetric chirp is studied within the real-time Dirac-Heisenberg-Wigner formalism. The reduced momentum spectrum and the reduced total number of the created particles under the quadratically symmetric chirped electric field are investigated in high- and low-frequency fields. Compared with that of the quadratically asymmetric chirped field in particular, it is found that the momentum spectrum under the quadratically symmetric chirped field exhibits the stronger oscillations and the higher peaks in both high- and low- frequency fields, and it shows an obvious widening only in the high-frequency field. It is also found that the total number of the created particles of the quadratically symmetric chirped field increases with the chirp, and it is nearly twice that of the quadratically asymmetric chirped field.

hep-ph↗

arXiv2017

Evolutionary of Online Social Networks Driven by Pareto Wealth Distribution and Bidirectional Preferential Attachment

Understanding of evolutionary mechanism of online social networks is greatly significant for the development of network science. However, present researches on evolutionary mechanism of online social networks are neither deep nor clear enough. In this study, we empirically showed the essential evolution characteristics of Renren online social network. From the perspective of Pareto wealth distribution and bidirectional preferential attachment, the origin of online social network evolution is analyzed and the evolution mechanism of online social networks is explained. Then a novel model is proposed to reproduce the essential evolution characteristics which are consistent with the ones of Renren online social network, and the evolutionary analytical solution to the model is presented. The model can also well predict the ordinary power-law degree distribution. In addition, the universal bowing phenomenon of the degree distribution in many online social networks is explained and predicted by the model. The results suggest that Pareto wealth distribution and bidirectional preferential attachment can play an important role in the evolution process of online social networks and can help us to understand the evolutionary origin of online social networks. The model has significant implications for dynamic simulation researches of social networks, especially in information diffusion through online communities and infection spreading in real societies.

physics.soc-ph↗