标题： 带弦云和非对易几何的带电四维高斯-博内黑洞的光学外观以及各种吸积轮廓的包围 显示英文标题

标题： The Optical Appearance of Charged Four-Dimensional Gauss-Bonnet Black Hole with Strings Cloud and Non-Commutative Geometry Surrounded by Various Accretions Profiles

摘要： 感谢事件视界望远镜（EHT）在$M87$星系中心释放的超大质量黑洞（BHs）图像。 在发现这一神秘天体之后，科学家们开始关注在不同引力背景下的BH阴影特征。 在这种情况下，我们研究了不同吸积流模型包围的BH阴影的光环和观测特性，然后在我们考虑的系统框架内探讨了模型参数对BH观测显示和时空结构的影响。 在发射轮廓不兼容的配置下，黑洞的图像包括观测亮度主要由直接辐射决定，而透镜环将对总观测通量做出较小的贡献，由于其指数狭窄性，光子环的贡献可以忽略不计。 更重要的是，所有发射轮廓的观测区域和特定强度会随着参数的变化而相应改变。 对于光学薄的吸积物质，我们分别分析了静态和下落吸积模型的阴影轮廓和特定强度。 我们发现，由于下落运动的多普勒效应，下落运动情况下阴影内部区域会比静态情况下更暗。 最后得出结论，这些发现支持BH状态参数的变化会改变时空几何的方式，从而影响BH阴影的动力学。 显示英文摘要

摘要： Thanks for the releasing image of supermassive black holes (BHs) by the event horizon telescope (EHT) at the heart of the $M87$ galaxy. After the discovery of this mysterious object, scientists paid attention to exploring the BH shadow features under different gravitational backgrounds. In this scenario, we study the light rings and observational properties of BH shadow surrounded by different accretion flow models and then investigate the effect of model parameters on the observational display and space-time structure of BHs in the framework of our considering system. Under the incompatible configuration of the emission profiles, the images of BHs comprise that the observed luminosity is mainly determined by direct emission, while the lensing ring will provide a small contribution of the total observed flux and the photon ring makes a negligible contribution due to its exponential narrowness. More importantly, the observed regions and specific intensities of all emission profiles are changed correspondingly under variations of parameters. For optically thin accreting matters, we analyze the profile and specific intensity of the shadows with static and infalling accretions models, respectively. We find that with an infalling motion the interior region of the shadows will be darker than in a static case, due to the Doppler effect of the infalling movement. Finally, it is concluded that these findings support that the change of BH state parameters will change the way of space-time geometry, thus affecting the BH shadows dynamics.