No Strong Evidence for Plasma Lensing in FRB 20240114A

Jiarui Niu; Xiaohui Liu; Nan Xu; Songyu Shen; Junshuo Zhang; Tiancong Wang; Pawan Kumar; Yuanhong Qu; Dejiang Zhou; Weiwei Zhu; Bing Zhang; He Gao; Dongzi Li; Jinlin Han; Di Li; Xuelei Chen; Kejia Lee; Ye Li; Weiyang Wang; Qiuyang Fu; Jiawei Jin; Yanqing Cai; Caisong Liu; Shuo Cao; Ziwei Wu; Heng Xu; Dengke Zhou; Longxuan Zhang; Wanjin Lu; Yi Feng; Chenhui Niu; Jiawei Luo; Rui Luo; Chunfeng Zhang; Shiqian Zhao; Chengwei Liang

arXiv · 2607.02939

No Strong Evidence for Plasma Lensing in FRB 20240114A

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Abstract

FRB~20240114A is an extremely active repeating fast radio burst for which plasma lensing has been proposed to explain its burst-rate variations, spectral evolution, and apparently ``carbon-copy'' burst pairs. Using FAST data and publicly available Parkes observations, we test this interpretation with a one-dimensional Gaussian plasma-lens model. Although the burst-rate enhancements can be fitted separately, the corresponding magnification peaks and demagnification troughs are offset by far more than predicted and show no consistent periodicity. Moreover, with more than 10,000 bursts detected, a few apparently ``carbon-copy'' pairs can readily occur by chance. The burst bandwidth is not systematically narrower during the proposed lensing interval, nor are the burst energies significantly enhanced during the predicted magnification interval. These results provide no compelling evidence that a single Gaussian plasma lens explains the observed variability, which is more likely dominated by intrinsic source activity.

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Jiarui Niu, Xiaohui Liu, Nan Xu, Songyu Shen, Junshuo Zhang, Tiancong Wang, Pawan Kumar, Yuanhong Qu, Dejiang Zhou, Weiwei Zhu, Bing Zhang, He Gao, Dongzi Li, Jinlin Han, Di Li, Xuelei Chen, Kejia Lee, Ye Li, Weiyang Wang, Qiuyang Fu, Jiawei Jin, Yanqing Cai, Caisong Liu, Shuo Cao, Ziwei Wu, Heng Xu, Dengke Zhou, Longxuan Zhang, Wanjin Lu, Yi Feng, Chenhui Niu, Jiawei Luo, Rui Luo, Chunfeng Zhang, Shiqian Zhao, Chengwei Liang. 2026-07-03. No Strong Evidence for Plasma Lensing in FRB 20240114A. https://arxiv.org/abs/2607.02939

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