Sub-parsec resolution cosmological simulations of star-forming clumps at high redshift with feedback of individual stars
Sub-parsec resolution cosmological simulations of star-forming clumps at high redshift with feedback of individual stars
复制标题
利用单个恒星的反馈对高红移恒星形成团块进行亚秒差距分辨率宇宙学模拟
DOI：
10.1093/mnras/stac2387
复制
发表时间：
2022
影响因子：
4.8
通讯作者：
Gilli, R.
中科院分区：
文献类型：
--
作者：
Calura, F.;Lupi, A.;Rosdahl, J.;Vanzella, E.;Meneghetti, M.;Rosati, P.;Vesperini, E.;Lacchin, E.;Pascale, R.;Gilli, R.
我们介绍了一套新的以亚pc分辨率放大的宇宙学模拟，旨在模拟极其微弱的，高度放大的恒星形成团，由于引力透镜检测到atz= 6.14。模拟包括来自单个大质量恒星（在超新星前和超新星阶段）的反馈，这些反馈是通过对恒星初始质量函数的随机直接采样产生的。我们采用了一种改进的“延迟冷却”反馈方案，专门用于防止在非常密集的气体（n ~ 103-105cm−3）中单个恒星注入的能量的人工辐射损失。恒星形成点的特征是最大密度约为105cm - 3，重力压力约为107K cm - 3，与最密集恒星聚集形成的局部湍流区域的值相对应。恒星总质量atz= 6.14 = 3.4，与观测系统的恒星质量符合得很好。质量最大的团块的质量为~ 100pc的质量大小。这些尺寸比观测到的大，也比其他透镜高红移团块的样品大，并且意味着平均密度比观测到的低一个数量级。在大小-质量平面上，我们的团块分布在观测到的高红移团块和本地dSph星系之间的一个序列中。
We introduce a new set of zoom-in cosmological simulations with sub-pc resolution, intended to model extremely faint, highly magnified star-forming stellar clumps, detected atz= 6.14 thanks to gravitational lensing. The simulations include feedback from individual massive stars (in both the pre-supernova and supernova phases), generated via stochastic, direct sampling of the stellar initial mass function. We adopt a modified ‘delayed cooling’ feedback scheme, specifically created to prevent artificial radiative loss of the energy injected by individual stars in very dense gas (n∼ 103–105cm−3). The sites where star formation ignites are characterized by maximum densities of the order of 105cm−3and gravitational pressuresPgrav/k >107K cm−3, corresponding to the values of the local, turbulent regions where the densest stellar aggregates form. The total stellar mass atz= 6.14 is 3.4, in satisfactory agreement with the observed stellar mass of the observed systems. The most massive clumps have masses ofand half-mass sizes of ∼100 pc. These sizes are larger than the observed ones, including also other samples of lensed high-redshift clumps, and imply an average density one orders of magnitude lower than the observed one. In the size–mass plane, our clumps populate a sequence that is intermediate between the ones of observed high-redshift clumps and local dSph galaxies.