发表机构
Columbia University; Max Planck Institute for Astrophysics; Ben-Gurion University（哥伦比亚大学; 马克斯·普朗克天体物理学研究所; 本-古里安大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究提出磁星爆发中电磁脉冲对磁层千赫兹波的受激散射机制，可产生宽窄谱快速射电暴，并解释其极端光度与微秒级成分。
AI 中文摘要
我们发现了一种能够产生宽谱和窄谱的快速射电暴（FRB）的发射机制。该机制在磁星爆发中起作用，磁星爆发从内磁层半径$r_0\sim 10^{7}$厘米处发射电磁脉冲。脉冲内的等离子体以洛伦兹因子$\Gamma(r)\approx r/r_0$向外加速。在半径$r\sim 10^{10}$厘米处退出磁层之前，脉冲穿过活跃磁星磁层中充满的环境千赫兹波。我们证明，这些波在脉冲内部经历受激散射，增频因子$\Gamma^2$将其转换为径向千兆赫兹辐射。这一过程将微小的千兆赫兹种子指数放大到与观测到的FRB一致的极端光度。产生的千兆赫兹爆发位于爆炸脉冲内部，这有助于它逃逸到远处的观测者。FRB的持续时间和能量由脉冲的持续时间和能量控制。在饱和发射状态下，预测的爆发包含一个超强的微秒级成分。
英文摘要
We find an emission mechanism for fast radio bursts (FRBs) capable of producing broad and narrow spectra. It operates in magnetar explosions, which launch an electromagnetic pulse from the inner magnetosphere at radii $r_0\sim 10^{7}$ cm. Plasma inside the pulse accelerates outward with Lorentz factor $Γ(r)\approx r/r_0$. Before exiting the magnetosphere at radius $r\sim 10^{10}$ cm, the pulse passes through ambient kHz waves that populate the magnetospheres of active magnetars. We show that the waves experience stimulated scattering inside the pulse, with the boost factor $Γ^2$ converting them into radial GHz radiation. This process exponentially amplifies tiny GHz seeds to extreme luminosities consistent with observed FRBs. The produced GHz burst rides inside the explosion pulse, which helps it escape to distant observers. The FRB duration and energy are controlled by the pulse duration and energy. In a saturated emission regime, the predicted burst contains an ultrastrong microsecond component.
Comments26 pages, 13 figures, submitted to ApJ
