标题： 由FRB 20190520B的压缩束相干曲率辐射产生的快速射电暴 显示英文标题

标题： Fast radio bursts generated by coherent curvature radiation from compressed bunches for FRB 20190520B

摘要： 快速射电暴（FRB）的辐射机制已被广泛研究，但仍然充满未知。相干辐射被认为是FRB机制中的关键组成部分，在特定情况下，带电粒子束也发挥了重要作用。在本研究中，我们提出了一种基于相干曲率辐射框架和磁化中子星的唯象学模型，同时考虑了由于磁层内软光子引起的逆康普顿散射（ICS）导致的流出粒子动能损失。通过整合粒子的ICS减速机制，我们假设在磁管/家族内可能存在粒子数密度的压缩效应，这可能有助于实现相干辐射所需的径向尺寸。该机制可能使沿弯曲磁场动态形成能够发射相干曲率辐射的粒子束成为可能。此外，我们从能量角度探讨了粒子束的形成。我们的讨论表明，在给定的参数空间内，粒子束的形成是可行的。最后，我们将此模型应用于FRB 20190520B，这是由FAST发现和监测到的最活跃的重复性FRB之一。几个观测现象得到了解释，包括基本特征、频率向下漂移以及某些动态频谱范围内的亮点。 显示英文摘要

摘要： The radiation mechanism of fast radio bursts (FRBs) has been extensively studied but still remains elusive. Coherent radiation is identified as a crucial component in the FRB mechanism, with charged bunches also playing a significant role under specific circumstances. In the present research, we propose a phenomenological model that draws upon the coherent curvature radiation framework and the magnetized neutron star, taking into account the kinetic energy losses of outflow particles due to inverse Compton scattering (ICS) induced by soft photons within the magnetosphere. By integrating the ICS deceleration mechanism for particles, we hypothesize a potential compression effect on the particle number density within a magnetic tube/family, which could facilitate achieving the necessary size for coherent radiation in the radial direction. This mechanism might potentially enable the dynamic formation of bunches capable of emitting coherent curvature radiation along the curved magnetic field. Moreover, we examine the formation of bunches from an energy perspective. Our discussion suggests that within the given parameter space the formation of bunches is feasible. Finally, we apply this model to FRB 20190520B, one of the most active repeating FRBs discovered and monitored by FAST. Several observed phenomena are explained, including basic characteristics, frequency downward drifting, and bright spots within certain dynamic spectral ranges.