论文标题
在一个四维的爱因斯坦 - 加斯河内黑洞周围的薄积聚盘
Thin Accretion Disk around a four-dimensional Einstein-Gauss-Bonnet Black Hole
论文作者
论文摘要
最近，Glavan和Lin [D. D.提出了一种新型的四维爱因斯坦 - 加斯 - 鲍尼特（4EGB）重力理论。 Glavan和C. Lin，物理。莱特牧师。 124，081301（2020）]，其中包括一个正规化的高斯式术语，使用高斯 - 骨耦合常数$α\至α/（d-4）$（限制$ d \ to 4 $）。该理论也已针对特定类别的Horndeski理论进行了重新重新，具有额外的标量自由度，并具有带有Lagrangian乘数的空间协变量版本，该版本可以消除标量模式。在这里，我们研究了4EGB重力中静态球形对称黑洞周围静态的吸积盘发出的电磁辐射的物理特性。为此，我们假设磁盘处于稳态和流体动力和热力学平衡中，因此发射的电磁辐射是黑色体光谱。我们详细研究了4EGB重力中高斯耦合常数$α$对磁盘的能量通量，温度分布和电磁光谱的影响。结果表明，随着参数$α$的增加，吸积盘的能量通量，温度分布和电磁光谱都增加了。此外，我们还表明，随着参数$α$的增长，积聚效率的提高。我们的结果表明，4EGB重力中的静态球形对称黑洞周围的薄积聚盘更热，更发光和更有效的效率，而Schwarzschild黑洞的质量更高，质量相同的$α$，虽然是凉爽的，更凉爽，更低的亮度，较小的亮度，并且对于负$ $α$ a $α$。
Recently a novel four-dimensional Einstein-Gauss-Bonnet (4EGB) theory of gravity was proposed by Glavan and Lin [D. Glavan and C. Lin, Phys. Rev. Lett. 124, 081301 (2020)] which includes a regularized Gauss-Bonnet term by using the re-scaling of the Gauss-Bonnet coupling constant $α\to α/(D-4)$ in the limit $D\to 4$. This theory also has been reformulated to a specific class of the Horndeski theory with an additional scalar degree of freedom and to a spatial covariant version with a Lagrangian multiplier that can eliminate the scalar mode. Here we study the physical properties of the electromagnetic radiation emitted from a thin accretion disk around the static spherically symmetric black hole in the 4EGB gravity. For this purpose, we assume the disk is in a steady-state and in hydrodynamic and thermodynamic equilibrium so that the emitted electromagnetic radiation is a black body spectrum. We study in detail the effects of the Gauss-Bonnet coupling constant $α$ in 4EGB gravity on the energy flux, temperature distribution, and electromagnetic spectrum of the disk. It is shown that with the increases of the parameter $α$, the energy flux, temperature distribution, and electromagnetic spectrum of the accretion disk all increase. Besides, we also show that the accretion efficiency increases as the growth of the parameter $α$. Our results indicate that the thin accretion disk around the static spherically symmetric black hole in the 4EGB gravity is hotter, more luminosity, and more efficient than that around a Schwarzschild black hole with the same mass for a positive $α$, while it is cooler, less luminosity, and less efficient for a negative $α$.
