AI 中文总结
该研究探究黑洞到白洞爆炸的抛射体扫过星际介质产生的非热电磁对应体，通过Weibel介导激波建模辐射过程，发现其余辉演化远快于经典长GRB，可作为区分其他快速瞬变的特征。
AI 中文摘要
我们研究黑洞到白洞转变产生的相对论性近各向同性抛射体扫过星际介质（ISM）时预期的非热电磁对应体。基于 prompt γ射线辐射的光球模型[Villani2026]，我们参数化了外部激波可用的动能Eiso=RkEγprompt，并利用Weibel介导的磁场[Weibel1959,MedvedevLoeb1999,SironiSpitkovsky2011]对产生的无碰撞前向激波进行建模。我们采用单区汤姆孙区近似，估算激波加速电子的同步辐射与同步自康普顿（SSC）辐射，包含逆康普顿冷却、克莱因-仁科抑制、自吸收及γ-γ不透明度，所有量均达到量级或一阶精度。对于示例参数（Eγprompt~10^44 erg，Rk=0.1，Γ0=100），电子为慢冷却，因此当p=2.5<3时，同步辐射谱在冷却频率νc处达到峰值，处于MeV到GeV范围且随时间变软；余辉演化时间从几分之一秒到数十秒，比相同能量、密度和洛伦兹因子下的经典长伽马射线暴（GRB）余辉快数个数量级，其持续时间、峰值能量和流量对Rk、nISM及εe、εB、ξe敏感。我们确定了本征峰值以下1 keV光子计数估计值超过标称探测阈值的参数区域，并讨论了相关特征——硬谱prompt闪光后快速、微弱、近似各向同性的瞬态余辉，无消色差喷流 break——这些特征可将该场景与短GRB、磁星巨耀发及其他快速瞬变区分，同时指出了限制其定量适用性的假设（仅前向激波动力学、单区汤姆孙区辐射、示例可探测性准则）。
英文摘要
We study the non-thermal electromagnetic counterpart expected when the relativistic, near-isotropic ejecta of a black-to-white hole transition sweep up the interstellar medium (ISM). Building on a photospheric model for the prompt $γ$-ray emission~\cite{Villani2026}, we parametrize the kinetic energy available for an external shock, $\eiso=R_k\egprompt$, and model the resulting collisionless forward shock with a Weibel-mediated field~\cite{Weibel1959,MedvedevLoeb1999,SironiSpitkovsky2011}. We estimate the synchrotron and synchrotron self-Compton (SSC) emission from shock-accelerated electrons in a one-zone, Thomson-regime approximation, including inverse-Compton cooling, Klein-Nishina suppression, self-absorption, and $γ$-$γ$ opacity, all at order-of-magnitude or first-order accuracy. For illustrative parameters ($\egprompt\sim10^{44}$ erg, $R_k=0.1$, $Γ_0=100$), the electrons are slow-cooling, so for $p=2.5<3$ the synchrotron spectrum peaks at the cooling frequency $ν_c$, in the MeV-to-GeV range and softening with time; the afterglow evolves in a fraction of a second to tens of seconds -- orders of magnitude faster than a classical long-duration GRB afterglow at comparable energy, density, and Lorentz factor -- with duration, peak energy, and flux depending sensitively on $R_k$, $\nism$, and $\epse,\epsB,\xie$. We identify parameter regions where a 1 keV photon-count estimate, below the intrinsic peak, exceeds a nominal detection threshold, and discuss features -- a fast, faint, roughly isotropic transient after a hard-spectrum prompt flash, without an achromatic jet break -- that may distinguish this scenario from short GRBs, magnetar giant flares, and other fast transients, while flagging the assumptions (forward-shock-only dynamics, one-zone Thomson-regime radiation, an illustrative detectability criterion) limiting its quantitative reach.
Comments15 pages, 7 figures,2 tables
