论文标题
AGN喷射膨胀气泡和簇内介质的复杂相互作用
The complex interplay of AGN jet-inflated bubbles and the intracluster medium
论文作者
论文摘要
我们使用Swift(一种平滑的粒子流体动力代码)来模拟活性银河核(AGN)喷气机膨胀的气泡的演变,以及它们与环境内室内培养基(ICM)的相互作用。这些喷气式喷气式会使喷气机关闭后变成气泡的裂片($ t = 50 $ myr)。关闭喷气机的几乎所有注入喷气机的能量都会很快转移到ICM,大约70美元的$ 70 $以热形式,其余的则以动力学为单位。在后期($ t> 500 $ MYR)我们找到以下内容:1)气泡抽出尾随的低渗透气体的尾随丝,类似于最近观察到的气泡,类似于那些,2)浮力的作用和细丝的提升占主导ICM中包含的休息。这些发现表明,反馈主要是通过将气体移动到较大的半径来进行。我们发现,这些细丝的升高通过降低中心密度并增加中心温度($ kpc $ 30 $ kpc),永久改变了ICM的热力学特性。我们建议喷气反馈不仅通过加热ICM(可能延迟冷却)进行,还通过与中央气体密度的升高相关的减少来进行。后者还延迟了冷却,除了减少可供冷却的气体量之上。
We use SWIFT, a smoothed particle hydrodynamics code, to simulate the evolution of bubbles inflated by active galactic nuclei (AGN) jets, as well as their interactions with the ambient intracluster medium (ICM). These jets inflate lobes that turn into bubbles after the jets are turned off (at $t=50$ Myr). Almost all of the energy injected into the jets is transferred to the ICM very quickly after they are turned off, with roughly $70$ per cent of it in thermal form and the rest in kinetic. At late times ($t>500$ Myr) we find the following: 1) the bubbles draw out trailing filaments of low-entropy gas, similar to those recently observed, 2) the action of buoyancy and the uplift of the filaments dominates the energetics of both the bubbles and the ICM and 3) almost all of the originally injected energy is in the form of gravitational potential energy, with the bubbles containing $15$ per cent of it, and the rest contained in the ICM. These findings indicate that feedback proceeds mainly through the displacement of gas to larger radii. We find that the uplift of these filaments permanently changes the thermodynamic properties of the ICM by reducing the central density and increasing the central temperature (within $30$ kpc). We propose that jet feedback proceeds not only through the heating of the ICM (which can delay cooling), but also through the uplift-related reduction of the central gas density. The latter also delays cooling, on top of reducing the amount of gas available to cool.