标题： 由重联驱动的M87*耀斑：质子同步辐射驱动的GeV辐射 显示英文标题

标题： Reconnection-driven Flares in M87*: Proton-synchrotron Powered GeV Emission

摘要： 在黑洞吸积流中间歇性形成的电流层中的磁重联是粒子加速和高能辐射的有希望的机制。最近提出，这种在通量爆发事件期间出现的层可以解释M87核心观测到的快速TeV耀斑。在这种情景中，由靠近重联层产生的高能电子-正电子对对吸积流中的软辐射进行逆康普顿散射被认为是最主要的辐射机制。然而，详细的计算表明，仅由对子产生的辐射无法解释费米观测台检测到的GeV辐射。在这项工作中，我们将解析估计与对子-质子等离子体的三维辐射粒子-网格模拟相结合，以表明GeV辐射可以通过电流片中加速的质子的同步辐射自然解释。尽管层中的质子含量尚不确定，但我们的模型在广泛的质子与对子数密度比范围内保持稳健。虽然质子在数量上不如对子占优势，但我们的模拟表明它们可以更有效地被加速，从而导致一个质子主导能量预算的自我调节稳定状态。最终，质子同步辐射约占总耗散功率的5%到20%。大部分以MeV光子的形式通过对子同步辐射辐射出来，较小的一部分通过逆康普顿散射以TeV光子的形式发射。 显示英文摘要

摘要： Magnetic reconnection in current layers that form intermittently in radiatively inefficient accretion flows onto black holes is a promising mechanism for particle acceleration and high-energy emission. It has been recently proposed that such layers, arising during flux eruption events, can power the rapid TeV flares observed from the core of M87. In this scenario, inverse Compton scattering of soft radiation from the accretion flow by energetic electron-positron pairs produced near the reconnection layer was suggested as the primary emission mechanism. However, detailed calculations show that radiation from pairs alone cannot account for the GeV emission detected by the Fermi observatory. In this work, we combine analytic estimates with 3D radiative particle-in-cell simulations of pair-proton plasmas to show that the GeV emission can be naturally explained by synchrotron radiation from protons accelerated in the current sheet. Although the exact proton content of the layer is uncertain, our model remains robust across a broad range of proton-to-pair number density ratios. While protons are subdominant in number compared to pairs, our simulations demonstrate that they can be accelerated more efficiently, leading to a self-regulated steady state in which protons dominate the energy budget. Ultimately, proton synchrotron emission accounts for approximately 5% to 20% of the total dissipation power. The majority is radiated as MeV photons via pair synchrotron emission, with a smaller fraction emitted as TeV photons through inverse Compton scattering.