First estimate of the local value of the baryonic streaming velocity
First estimate of the local value of the baryonic streaming velocity
复制标题
重子流速度局部值的首次估计
DOI：
10.1093/mnras/stad350
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发表时间：
2023
影响因子：
4.8
通讯作者：
Hartwig Tilman
中科院分区：
文献类型：
--
作者：
Uysal Bet?l;Hartwig Tilman
一些研究表明重子和暗物质之间的相对流动速度（SV）对结构形成的影响。我们第一次限制了银河系形成所在的 SV 的局部值。我们使用半解析模型a-sloth来模拟类银河系星系的形成。卡特彼勒模拟中的暗物质合并树的质量和时间高分辨率使我们能够准确地模拟高红移下最小祖晕中的恒星形成。 a-slot 的高效半解析性质允许我们使用不同的局部 SV 值运行许多模拟。我们对 SV 影响的研究表明，它延迟了高红移下的恒星形成。然而，当红移 z = 0 时，SV 对银河系及其卫星的总恒星质量没有影响。我们发现极度贫金属和超贫金属恒星受到 SV 的影响，因此可以用来限制其局部值。 SV 的局部最优值为 ，它基于四个独立的可观测值。我们进一步发现SV减少了发光银河系卫星的数量，但这种减少不足以解决卫星失踪的问题。
Several studies have shown the influence of the relative streaming velocity (SV) between baryons and dark matter on the formation of structures. For the first time, we constrain the local value of the SV in which the Milky Way was formed. We use the semi-analytical modela-slothto simulate the formation of Milky Way-like galaxies. The high resolution in mass and time of the dark matter merger trees from the Caterpillar simulation enables us to accurately model star formation in the smallest progenitor haloes at high redshift. The efficient semi-analytical nature ofa-slothallows us to run many simulations with various values of the local SV. Our investigation on the influence of the SV shows that it delays star formation at high redshift. However, at redshift z = 0, the SV has no effect on the total stellar mass in the Milky Way nor its Satellites. We find that extremely metal-poor and ultra metal-poor stars are affected by the SV and can hence be used to constrain its local value. The local optimal value of the SV is, which is based on four independent observables. We further find that the SV decreases the number of luminous Milky Way satellites, but this decrease is not enough to solve the missing satellite problem.