A high fidelity Milky Way simulation with Kraken, Gaia-Enceladus, and Sequoia analogues: clues to their accretion histories
A high fidelity Milky Way simulation with Kraken, Gaia-Enceladus, and Sequoia analogues: clues to their accretion histories
复制标题
用 Kraken、Gaia-Enceladus 和 Sequoia 类似物进行的高保真银河系模拟：它们吸积历史的线索
DOI：
10.1093/mnras/stad2832
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发表时间：
2023
影响因子：
4.8
通讯作者：
García-Bethencourt G
中科院分区：
文献类型：
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作者：
García-Bethencourt G
在一个模拟的银河系般的星系，我们确定和分析类似的盖亚-土卫二（GE），海怪，红杉合并，每个匹配非常好的观测结果，包括在速度和化学丰度空间，和它们的分布在thejz能量平面。Kraken类似物是最早的合并，具有最高的总质量比。与以前的研究一致，它在吸积时与旧的situstars在化学上是无法区分的。在我们的模拟中，GE和Sequoia类似事件在相似的时间发生吸积，都是沿着丝状物，但来自主星系的相对两侧。GE和红杉类似物的平均恒星年龄都是相似的，从我们的模拟结果中，我们看到它们可以是独立的实体，并且仍然自然地再现了目前所观察到的恒星残骸的性质，包括红杉类似物残骸恒星的显着逆行速度以及两个星系通过化学丰度空间的轨道差异。我们的研究结果提供了有关这三个合并事件的属性的支持信息，并首次表明它们都可以用完全的宇宙学模拟再现，为银河系的形成提供了一个可能的自洽演化途径。
Within a simulated Milky Way-like galaxy, we identify and analyse analogues of the Gaia-Enceladus (GE), Kraken, and Sequoia mergers that each matches remarkably well observational results, including in velocity and chemical abundance space, and their distributions in thejz-Energy plane. The Kraken analogue is the earliest merger and has the highest total mass ratio. Consistent with previous studies, it is chemically indistinguishable from oldin situstars at the time of its accretion. The GE and Sequoia analogue events accrete at similar times in our simulation, both along filaments but from opposite sides of the main galaxy. The mean stellar ages of the GE and Sequoia analogues are both similar and, from our simulation results, we see that they can be separate entities and still naturally reproduce the observed properties of their stellar remnants at the present day, including the significant retrograde velocities of the Sequoia analogue remnant stars and the difference in the tracks of the two galaxies through chemical abundance space. Our results provide supporting information about the properties of these three merger events, and show for the first time that they can all be reproduced with a fully cosmological simulation, providing a possible self-consistent evolutionary pathway for the Milky Way’s formation.