论文标题
在Starburst的大爆炸中加速星系风
Accelerating Galaxy Winds During the Big Bang of Starbursts
论文作者
论文摘要
我们开发了一种新的方法来推断银河流出的时间，几何和能量性能，通过将恒星光谱建模结合起来推断出星状爆炸年龄，以及测量速度的吸收线。如果在Starburst事件中随时间加速风，那么这两个测量值使我们能够解决风半径，类似于长度尺度和大型Bang宇宙学中的Hubble参数。这种风半径是风理学中至关重要但难以约束的参数。我们在z = 0.05-0.44处使用87个星爆星系的光谱演示了该方法，发现在〜10 myr中，风在整个星爆阶段加速，并成长为典型的半径。质量流速随时间而迅速增加，质量加载因子在约10个MYR时超过统一 - 虽然仍在加速，但气体可能会与局部电位解脱，并富含圆形型培养基。我们对恒星风和超新星可用的机械能进行建模，并估计在早期的凉爽流出中，量可忽略不计。但是，能量沉积迅速增加，预算的约10％在10 MYR时的凉爽流量中占了，类似于最近的一些流体动力学模拟。我们讨论如何开发该模型，尤其是对于高红移星系。
We develop a new method to infer the temporal, geometric, and energetic properties of galaxy outflows, by combining stellar spectral modeling to infer starburst ages, and absorption lines to measure velocities. If winds are accelerated with time during a starburst event, then these two measurements enable us to solve for the wind radius, similarly to length scales and the Hubble parameter in Big Bang cosmology. This wind radius is the vital, but hard-to-constrain parameter in wind physics. We demonstrate the method using spectra of 87 starburst galaxies at z=0.05-0.44, finding that winds accelerate throughout the starburst phase and grow to typical radii of ~1 kpc in ~10 Myr. Mass flow rates increase rapidly with time, and the mass-loading factor exceeds unity at about 10 Myr - while still being accelerated, the gas will likely unbind from the local potential and enrich the circumgalactic medium. We model the mechanical energy available from stellar winds and supernovae, and estimate that a negligible amount is accounted for in the cool outflow at early times. However, the energy deposition increases rapidly and ~10% of the budget is accounted for in the cool flow at 10 Myr, similar to some recent hydrodynamical simulations. We discuss how this model can be developed, especially for high-redshift galaxies.
