论文标题
从$ l _ {\ ast} $ galaxies cosmic-ray驱动的流向MPC量表
Cosmic-Ray Driven Outflows to Mpc Scales from $L_{\ast}$ Galaxies
论文作者
论文摘要
我们研究了宇宙射线（CRS）对圆周和半乳酸间介质（CGM/IGM）中星系星系的流出的影响，在高分辨率的，完全化学的FIRE-2模拟中（考虑机械和辐射恒星的磁场，磁场，磁场，Anisotrocicic Ductuction/viscsution/cr diffusion/cr diffusion和cromprofe and creting and creting and creting and creting和creting和creting和creting and crompersing and creting和creting和creting和creting和creting和creting和creting和creting和creting和creting; We showed previously that massive ($M_{\rm halo}\gtrsim 10^{11}\,M_{\odot}$), low-redshift ($z\lesssim 1-2$) halos can have CR pressure dominate over thermal CGM pressure and balance gravity, giving rise to a cooler CGM with an equilibrium density profile.这极大地改变了流出。缺乏CR，在磁盘附近的大量光环“陷阱”银河流出中的高气热压，因此它们回收了。在此处建模的Supernovae中，CRS注入了CR，低压光环允许“逃脱”，CR压力梯度连续加速了该材料的“快速”流出，而在“快速”流出中，大半径的低密度气体被加速到“慢速”中，延伸至$> $ $> $> $> $ mpc。 CGM/IGM流出形态发生了根本性的改变：它们大多变成体积填充（在薄平面层中流入），并且从磁盘到$ $ $ MPC的双色调相干。 CR驱动的流出主要是很酷的（$ t \ sim10^{5} \，$ k）和低速性。所有这些效果都在下光环质量（$ \ Lessim 10^{11} \，M _ {\ odot} $）或更高的红移（$ z \ gtrsim 1-2 $）上削弱并最终消失，反映了外部卤代中CR与热+引力的比率。我们提出了一个简单的分析模型，该模型解释了上述所有现象。
We study the effects of cosmic rays (CRs) on outflows from star-forming galaxies in the circum and inter-galactic medium (CGM/IGM), in high-resolution, fully-cosmological FIRE-2 simulations (accounting for mechanical and radiative stellar feedback, magnetic fields, anisotropic conduction/viscosity/CR diffusion and streaming, and CR losses). We showed previously that massive ($M_{\rm halo}\gtrsim 10^{11}\,M_{\odot}$), low-redshift ($z\lesssim 1-2$) halos can have CR pressure dominate over thermal CGM pressure and balance gravity, giving rise to a cooler CGM with an equilibrium density profile. This dramatically alters outflows. Absent CRs, high gas thermal pressure in massive halos "traps" galactic outflows near the disk, so they recycle. With CRs injected in supernovae as modeled here, the low-pressure halo allows "escape" and CR pressure gradients continuously accelerate this material well into the IGM in "fast" outflows, while lower-density gas at large radii is accelerated in-situ into "slow" outflows that extend to $>$Mpc scales. CGM/IGM outflow morphologies are radically altered: they become mostly volume-filling (with inflow in a thin mid-plane layer) and coherently biconical from the disk to $>$Mpc. The CR-driven outflows are primarily cool ($T\sim10^{5}\,$K) and low-velocity. All of these effects weaken and eventually vanish at lower halo masses ($\lesssim 10^{11}\,M_{\odot}$) or higher redshifts ($z\gtrsim 1-2$), reflecting the ratio of CR to thermal+gravitational pressure in the outer halo. We present a simple analytic model which explains all of the above phenomena.
