AI 中文总结
该研究基于CLASSY巡天的17个星系外流，通过紫外吸收线辐射传输建模，分析外流的运动学与空间分布，推导加载因子并与模拟对比，发现外流特性与恒星质量、恒星族年龄相关。
AI 中文摘要
恒星形成星系会驱动大质量外流，这类外流通过调节反馈机制、影响周围介质的动力学，在星系演化中发挥重要作用。测量星系外流速率对于量化反馈效率，以及确定沉积到周星系介质中的质量、动量和能量的量至关重要。本文中，我们研究了CLASSY巡天中的17个星系外流，采用了M. Huberty等人（2024）提出的紫外吸收线辐射传输建模，以探究它们的空间分布和运动学特性。我们研究了SiII、SiIII和SiIV这三种电离态，它们分别示踪外流的冷相和暖相，发现SiII示踪的风通常与更暖的SiIII和SiIV示踪的风表现出不同的特性。我们推导了质量、动量和能量加载因子，发现这些因子与恒星质量呈反比关系。我们发现，我们对质量和动量加载因子的测量结果与流体动力学FIRE-2模拟一致。我们对风的速度剖面进行建模，剖面的平均最大速度达到620 km/s，与CGOLS的流体动力学模拟结果相符。我们还研究了外流特性与SED拟合得到的恒星族年龄之间的关系，发现与年轻恒星形成区相关的外流更可能具有以较冷气体为主的柱密度，且质量外流速率随半径增大而降低。
英文摘要
Star-forming galaxies drive massive outflows that play an important role in galaxy evolution by regulating feedback and influencing the dynamics of surrounding media. Measuring galactic outflow rates is essential for quantifying feedback efficiency and the amount of mass, momentum, and energy deposited into the circumgalactic medium. In this paper, we examine 17 galactic outflows from the CLASSY survey with radiative transfer modeling of UV absorption lines presented in M. Huberty et al. (2024), to study their spatial distributions and kinematic properties. We study the SiII, SiIII, and SiIV ionization states that trace the cool and warm phases of the outflows and find that SiII traced winds generally behave differently than the warmer SiIII and SiIV traced winds. We derive the mass, momentum, and energy loading factors, which we find scale inversely proportional to stellar mass. We find that our measurements of the mass and momentum loading factors are in agreement with the hydrodynamic FIRE-2 simulations. We model the velocity profiles of the winds, with profiles reaching a maximum velocity of 620 km/s on average, in agreement with hydrodynamic simulations from CGOLS. We also investigate the relationship between outflow properties and the age of the stellar population from SED fitting. We find that outflows associated with young star forming regions are more likely to have a column density dominated by cooler gas and have mass outflow rates which decrease with radius.
CommentsAccepted to ApJ, 15 pages, 5 figures
