重复暴FRB 20201124A的观测和模型ArticlePublished: 21 September 2022A fast radio burst source at a complex magnetized site in a barred galaxyH. Xu, J. R. Niu, P. Chen, K. J. Lee, W. W. Zhu, S. Dong, B. Zhang, J. C. Jiang, B. J. Wang, J. W. Xu, C. F. Zhang, H. Fu, A. V. Filippenko, E. W. Peng, D. J. Zhou, Y. K. Zhang, P. Wang, Y. Feng, Y. Li, T. G. Brink, D. Z. Li, W. Lu, Y. P. Yang, R. N. Caballero, …J. H. Zou Show authorsNature volume 609, pages685–688 (2022)Cite this articleAbstract
Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1,2,3. Recent observations of a Galactic FRB4,5,6,7,8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth–Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10,11,12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.https://www.nature.com/articles/s41586-022-05071-8 
a, 暴的数目, b, 爆发率, c, RM, d. 线偏振度, e. 圆偏振度, f. 观测时间. 后面灰色的是观测了, 但没有爆发. 但也没有对它周期爆发的报道.
DM的值的变化
圆圈处是它的位置. 用EVN测到的.
也有一些down drifting的暴
RM看起来还有些规律
Wang et al还能解释这个规律 https://doi.org/10.1038/s41467-022-31923-y 
