LYRA II: Cosmological dwarf galaxy formation with inhomogeneous Population III enrichment
LYRA II: Cosmological dwarf galaxy formation with inhomogeneous Population III enrichment
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天琴座 II：宇宙学矮星系的形成与不均匀的族 III 富集
DOI：
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
V. Springel
中科院分区：
文献类型：
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作者：
T. Gutcke;R. Pakmor;T. Naab;V. Springel
我们提出了 2 × 10 9 M (cid:12) 晕质量宇宙学矮星系的模拟，该星系在 4 个太阳质量气体分辨率下运行到 z = 0，并具有解析的超新星反馈。我们比较了来自 III 族恒星的不均匀化学富集的三种简单子网格实现，并将它们与来自本星系群矮星系的约束进行比较。所采用的模型 LYRA 是为移动网格代码 AREPO 构建的新型高分辨率星系形成模型，其特点是解析的多相星际介质、单星和单个超新星事件。由此产生的再电离遗迹的特点是恒星形成历史很短（< 1. 5 Gyr），并且会因猛烈的反馈爆发而反复陷入停滞状态。由于在 z ≈ 4 处合并，然后在 z ≈ 0 处再次合并，恒星形成会在短时间内重新点燃。持续气体吸积后为 2 − 0。我们的模型 z = 0 星系与本群矮星系的恒星质量、大小、恒星运动学和金属丰度关系很好地匹配。在任何版本的模型中，暗物质剖面都没有表现出核心。我们证明，第三族恒星的主晕质量影响矮星系的聚集历史。这通过祖晕中最初的气体塌缩来体现，影响恒星成分的中心密度，并通过发光子结构的吸积来体现。
We present the simulation of a 2 × 10 9 M (cid:12) halo mass cosmological dwarf galaxy run to z = 0 at 4 solar mass gas resolution with resolved supernova feedback. We compare three simple subgrid implementations for the inhomogeneous chemical enrichment from Population III stars and compare them to constraints from Local Group dwarf galaxies. The employed model, LYRA , is a novel high resolution galaxy formation model built for the moving mesh code AREPO , which is marked by a resolved multi-phase interstellar medium, single stars and individual supernova events. The resulting reionization relic is characterized by a short ( < 1 . 5 Gyr) star formation history that is repeatedly brought to a standstill by violent bursts of feedback. Star formation is reignited for a short duration due to a merger at z ≈ 4 and then again at z ≈ 0 . 2 − 0 after sustained gas accretion. Our model z = 0 galaxy matches the stellar mass, size, stellar kinematics and metallicity relations of Local Group dwarf galaxies well. The dark matter profile does not exhibit a core in any version of the model. We show that the host halo masses of Population III stars affect the assembly history of dwarf galaxies. This manifests itself through the initial gaseous collapse in the progenitor halos, affecting the central density of the stellar component and through the accretion of luminous substructure.