The team from the National Astronomical Observatories of the Chinese Academy of Sciences, under the FAST priority major scientific project for rapid radio bursts, utilized the Five-hundred-meter Aperture Spherical radio Telescope (FAST), located in Guizhou Province, China, to observe FRB20201124A. For the first time, they discovered a polarization position angle jump phenomenon within a fast radio burst (FRB). The findings were published on September 10, 2024, in The Astrophysical Journal Letters. This phenomenon had previously only been observed in pulsars. We detected three bursts with approximately 90-degree polarization angle jumps. Given that the timescale over which these jumps occurred is very short (about 1 millisecond), as illustrated in the figure, it implies that the emission region must be extremely small, smaller than the light cylinder of most pulsars, providing new constraints on the physical conditions of the FRB emission region. These jump phenomena are strikingly similar to observations in pulsars, suggesting that FRB emissions may originate from a highly magnetized plasma environment, offering strong support for the magnetar origin of repeating FRBs.

REFERENCE：FAST首次观测到快速射电暴偏振位置角跳变揭示了其辐射机制--中国科学院国家天文台

PAPER：https://iopscience.iop.org/article/10.3847/2041-8213/ad7023/pdf