标题： 光子表面、阴影和引力中耦合标量场的吸积盘 显示英文标题

标题： Photon surfaces, shadows and accretion disks in gravity with minimally coupled scalar field

摘要： 在本文中，我们对由爱因斯坦引力中最近获得的两个旋转几何结构描述的黑洞模拟器的可能可观测图像进行了顺序研究，这些几何结构与标量场最小耦合。其中一种称为“类似克尔”（KL）的结构可以被视为旋转费舍尔-贾尼斯-纽曼-温尼科耳（FJNW）解的一个合法替代方案，而另一种（TSL）则是汤米马茨-萨托解的标量推广。与之前版本的旋转FJNW不同，这些解确实满足系统的运动方程。我们的研究包括对各种物体角动量和标量电荷值的赤道圆轨道、光子区域、引力阴影以及薄吸积盘辐射的分析和数值计算。发现TSL解在所有有效参数值下都能以高精度模拟克尔。克尔和TSL情况下阴影偏离圆形的最大差异不超过1%，并且符合M87*的实验观测数据。然而，接近极端的物体显示出的吸积盘观测喷流亮度峰值比克尔黑洞小两倍。对于小标量电荷值，实验数据也无法排除KL解。随着标量电荷的增加，光学特性会发生显著变化。阴影可能会变得多重连通、强烈扁平，光子区域不会隐藏奇点，因此应将其归类为强奇点。 显示英文摘要

摘要： In this article, we conduct a sequential study of possible observable images of black hole simulators described by two recently obtained rotating geometries in Einstein gravity, minimally coupled to a scalar field. One of them, "Kerr-like" (KL), can be seen as a legitimate alternative to the rotating Fisher-Janis-Newman-Winicour (FJNW) solution, and the other (TSL) is a scalar generalization of the Tomimatsu-Sato solution. Unlike the previous version of the rotating FJNW, these solutions do indeed satisfy the system's equations of motion. Our study includes both analytical and numerical calculations of equatorial circular orbits, photon regions, gravitational shadows, and radiation from thin accretion disks for various values of the object's angular momentum and scalar charge. The TSL solution was found to simulate Kerr for all valid parameter values with high accuracy. The maximum difference between the deviations of shadows from a circle for the Kerr and TSL cases does not exceed 1% and fits into the experimental observational data M87*. However, near-extreme objects show two times smaller peak values of the observed outflow luminosity of the accretion disk than for the Kerr black hole. The KL solution cannot be ruled out by the experimental data for small values of the scalar charge either. As the scalar charge increases, the optical properties change dramatically. The shadow can become multiply connected, strongly oblate, and the photon region does not hide the singularity, so it should be classified as a strong singularity.