发表机构
Universidad Politécnica de Madrid; Instituto de Física Teórica UAM-CSIC; Universidad Autónoma de Madrid; Escuela Politécnica Superior, Universidad San Pablo-CEU; Utah State University（马德里理工大学; UAM-CSIC理论物理研究所; 马德里自治大学; 圣保罗ceu大学高等理工学院; 犹他州立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究探讨Sgr A*的磁彭罗斯过程，发现其可将质子加速至PeV能量，预测的伽马射线和中微子信号可通过SWGO等多信使设备观测，确立了该过程作为黑洞能量提取的可观测机制。
AI 中文摘要
磁彭罗斯过程（Magnetic Penrose Process，MPP）是从磁化克尔黑洞（BH）提取旋转能量的最有效机制之一，能使带电粒子达到极高能量。我们研究银心（GC）超大质量黑洞人马座A*（Sgr A*）中的该过程，重点关注其超高效能区域，在此区域内中子会在黑洞能层内发生β衰变。作为一项关键创新，我们直接从核反应运动学计算吸积流中的中子产生谱，并追踪克尔时空中的中子轨迹，以确定到达能层并发生MPP的粒子群。基于该粒子群，我们推导了加速质子的谱，表明Sgr A*可将质子加速至PeV能量，进一步支持其作为银河PeVatron候选体的解释。我们还计算了逃逸质子在中心分子区发生强子相互作用产生的伽马射线和中微子辐射。预测的伽马射线通量呈现出独特的谱特征，可作为MPP的观测信号，且可能对H.E.S.S.和HAWC探测到的甚高能辐射产生不可忽略的贡献。相关中微子通量仍低于IceCube推断的银河弥散分量，但仍可能对银心的高能辐射有贡献。值得注意的是，在本文考虑的所有场景中，预测信号均处于SWGO的预计灵敏度范围内，对于部分模型，仅比名义CTAO灵敏度低几个量级，而KM3NeT/ARCA和IceCube-Gen2将提供补充性检验。我们的结果确立了MPP作为一种可观测的黑洞旋转能量提取机制，建立了视界尺度物理与多信使观测之间的直接联系，该联系可推广至其他磁化黑洞。
英文摘要
The magnetic Penrose process (MPP) is one of the most efficient mechanisms for extracting rotational energy from a magnetized Kerr black hole (BH), enabling charged particles to reach very-high energies. We investigate this process in Sagittarius A* (Sgr A*), the supermassive BH at the Galactic center (GC), focusing on its ultra-high-efficiency regime, in which neutrons undergo beta decay inside the BH ergosphere. As a key novelty, we compute the neutron production spectrum in the accretion flow directly from the nuclear reaction kinematics and follow neutron trajectories in the Kerr spacetime to determine the population that reaches the ergosphere and undergoes the MPP. From this population, we derive the spectrum of accelerated protons and show that Sgr A* can accelerate them up to PeV energies, strengthening its interpretation as a candidate Galactic PeVatron. We further compute the gamma-ray and neutrino emission produced through hadronic interactions of the escaping protons in the Central Molecular Zone. The predicted gamma-ray fluxes exhibit distinctive spectral features that could provide an observational signature of the MPP and may constitute a non-negligible contribution to the very-high-energy emission detected by H.E.S.S. and HAWC. The associated neutrino fluxes remain below the diffuse Galactic component inferred by IceCube, but may still contribute to the high-energy emission from the GC. Remarkably, the predicted signals lie within the projected sensitivity of SWGO for all scenarios considered here and, for some models, only a factor of a few below the nominal CTAO sensitivity, while KM3NeT/ARCA and IceCube-Gen2 will provide complementary tests. Our results establish the MPP as an observable mechanism for extracting BH rotational energy, providing a direct connection between horizon-scale physics and multimessenger observations that can be extended to other magnetized BHs.
Comments27 pages, 12 figures and 2 tables. Comments welcome
