星盘碰撞引发的潮汐失能事件延迟射电暴发

越来越多的潮汐失能事件（TDE）显示出在光学或红外暴发后多年才升起的射电辐射，这表明存在延迟的外流活动。在某些事件中，外流被推断为较慢的（$\sim 0.02 \, c$）且质量较大的（$\gtrsim 0.01-0.1 M_{\odot}$），这对诸如延迟喷流和盘状态转变等模型构成挑战。我们提出了一种新的机制来解释此类延迟外流：TDE 盘与围绕黑洞运行的预存在的极端质量比值引力波相互作用（EMRI）的重复碰撞。在此场景下，延迟反映了最初紧凑的TDE盘扩张并拦截EMRI轨道所需的黏性时间，而非延迟喷流启动或侧向观察效应。一旦星盘碰撞开始，重复的冲击会以与轨道速度相当的速度（$v_{\rm w} \sim 0.02-0.1c$）喷发外流。我们发展了一个描述扩散盘和EMRI引起的质量损失耦合演化的时间依赖模型，识别了外流由盘材料或被剥离的恒星碎片主导的 regime。 Depending on disk viscosity, orbital period, and collision efficiency, masses $\sim (10^{-3}-1) \, \rm M_\odot$ can be launched with energies up to $10^{51} \rm \, erg$, years after the TDE. These outflows produce radio emission through interaction with circumnuclear material or earlier TDE ejecta, consistent with observed late-time radio re-brightening. This model predicts a connection between delayed radio flares and EMRI-hosting systems, potentially including those exhibiting quasi-periodic eruptions (QPEs) powered by star-disk collisions, though the conditions for bright radio flares may not always match those necessary for detectable QPEs.