标题： 超音速湍流在原初晕中：与没有流速度的比较 显示英文标题

标题： Supersonic Turbulence in Primordial Halos: A Comparison With and Without The Stream Velocity

摘要： 湍流在调节分子云中的恒星形成中起着关键作用，并且在模拟原始晕中观测到，这些晕中包含原初第三代（Pop III）恒星。 再结合时期，重子物质和暗物质之间的相对速度被认为是早期宇宙中湍流的来源。 在本文中，我们使用高分辨率宇宙学模拟，研究这种流速如何影响原始晕内的湍流，模拟覆盖红移范围从$z = 30$到$z = 20$。 我们发现，在固定红移下，流速增强了低质量晕（$M \lesssim 10^6 \ \mathrm{M_\odot}$）中的湍流，而抑制了高质量晕（$M \gtrsim 10^6 \ \mathrm{M_\odot}$）中的湍流。 低质量晕中的增强可能来自于流速引入的剩余动能，而高质量晕中的抑制可能来自于流入的吸积驱动湍流的减少。 这种质量依赖的湍流调制表明，在存在流速的情况下，原始晕内的初始条件发生了改变，可能会对其碎片化以及由此产生的恒星形成产生影响。 显示英文摘要

摘要： Turbulence plays a critical role in regulating star formation in molecular clouds and is also observed in simulations of primordial halos that host Population III (Pop III) stars. The relative velocity between baryons and dark matter at the time of recombination is thought to be a source of turbulence in the early universe. In this paper, we study how this stream velocity affects the turbulence inside primordial halos using high-resolution cosmological simulations across the redshift range of $z = 30$ to $z = 20$. We find that at a fixed redshift, the stream velocity enhances turbulence in low-mass halos ($M \lesssim 10^6 \ \mathrm{M_\odot}$) and suppresses it for high-mass halos ($M \gtrsim 10^6 \ \mathrm{M_\odot}$). The enhancement in low-mass halos likely arises from residual kinetic energy introduced by the stream velocity, while the suppression in high-mass halos likely arises from a reduction in inflowing accretion-driven turbulence. This mass-dependent modulation of turbulence suggests that the initial conditions inside primordial halos are altered in the presence of the stream velocity, potentially influencing their fragmentation and the resulting star formation.