Swift J1727.8-1613在2023年耀发状态期间高能超出的演化
Evolution of the High-Energy Excess in Swift J1727.8-1613 during Its 2023 Flare State
- Wuhan University（武汉大学）
- Nanjing University（南京大学）
- Shanghai Astronomical Observatory, Chinese Academy of Sciences (CAS)（中国科学院上海天文台）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究利用Insight-HXMT和INTEGRAL/ISGRI数据，揭示Swift J1727.8-1613在2023年耀发期间存在高能超出，其电子能量供应由热加热转为非热加速，并与瞬态喷流抛射相关联。
AI中文摘要：
我们利用Insight-HXMT和INTEGRAL/ISGRI的联合观测，覆盖2-500 keV能段，研究了Swift J1727.8-1613在2023年耀发状态期间高能超出的演化。使用包含热康普顿化和盘反射的模型对宽带光谱进行拟合，在约150 keV以上留下了系统性正残差。加入幂律分量改善了拟合，得到的光子指数为2.08-2.61，表明超出热康普顿化连续谱的高能超出在整个耀发状态期间都存在。我们还表明，所有光谱都可以用混合康普顿化模型eqpair很好地描述，而无需任何额外的高能分量。拟合结果表明，电子的能量供应从以热加热为主转变为以非热加速为主，并且电子注入光谱在耀发状态开始附近急剧变陡。在这种演化过程中，射电光谱指数从约零变为负值，同时伴随着三个瞬态喷流结的抛射。基于这种时间关联，我们讨论了我们的光谱分析所指示的非热功率增加与瞬态喷流抛射之间可能存在的联系。
英文摘要：
We investigate the evolution of the high-energy excess in Swift J1727.8-1613 during its 2023 flare state using joint Insight-HXMT and INTEGRAL/ISGRI observations covering 2-500 keV. Fits to the broadband spectra with a model including thermal Comptonization and disk reflection leave systematic positive residuals above ~150 keV. Adding a power-law component improves the fits and yields photon indices of 2.08-2.61, demonstrating that the high-energy excess beyond the thermal Comptonization continuum is present throughout the flare state. We also show that all spectra can be well described by the hybrid Comptonization model eqpair, without requiring any additional high-energy component. The fitting results indicate that the energy supply to the electrons transitions from predominantly thermal heating to non-thermal acceleration, and that the electron injection spectrum steepens abruptly near the onset of the flare state. During this evolution, the radio spectral index changes from approximately zero to negative values, accompanied by the ejection of three transient jet knots. Based on this temporal association, we discuss a possible connection between the increase in non-thermal power indicated by our spectral analysis and the ejection of the transient jet.
