AI 中文总结
研究LIGO-Virgo-KAGRA探测的二元系统合并前阶段，通过求解磁化Kerr时空中带电粒子测地线方程，探索合并残余参数空间，揭示三种加速机制，给出34个高自旋引力波事件最大能量计算结果，确立磁化二元合并为UHECRs有希望来源并提供定量预测。
AI 中文摘要
我们研究了通过Bañados--Silk--West（BSW）机制在LIGO-Virgo-KAGRA探测到的二元系统合并前阶段产生超高能粒子的情况。通过求解磁化Kerr时空中带电粒子的测地线方程，磁场强度为\(B \sim 10^{12}\) - \(10^{14}\) G，我们证明了视界附近的碰撞可以达到质心能量\(E_{\mathrm{cm}} \sim 10^{18}\) - \(10^{20}\) eV，使其稳稳处于超高能宇宙射线（UHECR）范围内。我们系统地探索了合并残余的参数空间，改变黑洞质量（\(M \sim 20\) - \(150\,M_\odot\)，典型的双黑洞群体）、无量纲自旋（\(\chi_f \sim 0.7\) - \(0.9\)）、磁场强度和粒子角动量。我们的分析揭示了三种不同的加速机制：重力主导机制（\(B < 10^{12}\) G），磁增强可忽略不计；过渡机制（\(10^{12}\) G \(\lesssim B \lesssim 10^{13}\) G），重力和磁效应相互竞争；磁主导机制（\(B > 10^{13}\) G），磁场将碰撞能量放大近一个数量级。对于34个具有高残余自旋（\(\chi_f > 0.7\)）的引力波事件，我们计算了可达到的最大能量，发现\(\chi_f \gtrsim 0.85\)且\(M \gtrsim 100\,M_\odot\)的系统可以达到\(E_{\mathrm{max}} \sim 10^{20}\) eV。我们的结果确立了磁化二元合并，特别是黑洞 - 中子星系统和双中子星合并中形成的合并后黑洞残余，作为UHECRs的有希望来源，并提供了将引力波可观测量与粒子加速效率联系起来的定量预测。
英文摘要
We study the production of ultra-high-energy particles via the Bañados--Silk--West (BSW) mechanism in the pre-merger phase of binary systems detected by LIGO-Virgo-KAGRA. By solving the geodesic equations for charged particles in magnetized Kerr spacetime with fields of $B \sim 10^{12}$--$10^{14}$~G, we demonstrate that collisions near the horizon can achieve center-of-mass energies $E_{\mathrm{cm}} \sim 10^{18}$-- $10^{20}$~eV, placing them firmly in the ultra-high-energy cosmic-ray (UHECR) range. We systematically explore the parameter space of merger remnants, varying black hole mass ($M \sim 20$--$150\,M_\odot$, characteristic of the binary black hole population), dimensionless spin ($χ_f \sim 0.7$--$0.9$), magnetic field strength, and particle angular momenta. Our analysis reveals three distinct acceleration regimes: a gravity-dominated regime ($B < 10^{12}$~G) with negligible magnetic enhancement; a transition regime ($10^{12}~\text{G} \lesssim B \lesssim 10^{13}~\text{G}$) where gravitational and magnetic effects compete; and a magnetic-dominated regime ($B > 10^{13}$~G) where fields amplify collision energies by nearly an order of magnitude. For the 34 gravitational-wave events with high remnant spins ($χ_f > 0.7$), we compute the maximum achievable energies, finding that systems with $χ_f \gtrsim 0.85$ and $M \gtrsim 100\,M_\odot$ can reach $E_{\mathrm{max}} \sim 10^{20}$~eV. Our results establish magnetized binary mergers, particularly black hole--neutron star systems and postmerger black hole remnants formed in binary neutron star coalescences, as promising sources of UHECRs and provide quantitative predictions linking gravitational-wave observables to particle acceleration efficiency.
Comments16 pages, 4 figures. Accepted for publication in Physical Review D
