The Dynamical and Chemical Evolution of Dwarf Spheroidal Galaxies with GEAR
The Dynamical and Chemical Evolution of Dwarf Spheroidal Galaxies with GEAR
复制标题
用 GEAR 研究矮椭球星系的动力学和化学演化
DOI：
10.1051/0004-6361/201117402
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发表时间：
2009
影响因子：
6.5
通讯作者：
P. Jablonka
中科院分区：
文献类型：
--
作者：
Y. Revaz;P. Jablonka;P. Jablonka
我们提出了完全并行的化学动力学树/SPH代码齿轮，它允许我们执行高分辨率的模拟和详细的化学诊断。从Gadget-2的公开版本开始，我们包括了对重子物理的复杂处理：气体冷却、恒星形成定律、化学演化和超新星反馈。我们在矮球星系(Dsps)的情况下验证了Gear的性能。我们的代码齿轮使系统的总能量收支在14Gyr上保持在5%以下，并用数值分辨率提供了很好的收敛结果。我们证明了在忽略宇宙膨胀的静态欧几里得空间中的dSphs模型是有效的。此外，我们还解决了该领域存在的一些悬而未决的问题，如dSphs的恒星质量分数及其与预测的暗物质晕质量函数的联系、超新星反馈的影响、恒星群的空间分布、恒星形成历史和化学丰度模式多样性的起源等。强烈的超新星驱动的风似乎与观测到的金属度和光度不相容。尽管新形成的恒星优先在星系中心部分被发现，但气体中的湍流运动可以迅速消除任何金属丰度梯度。DSph性质的多样性与总质量的范围以及中心密度的色散范围有关，这也可以在Lambda CDM宇宙卫星产生的晕中看到。
We present the fully parallel chemo-dynamical Tree/SPH code GEAR, which allows us to perform high resolution simulations with detailed chemical diagnostics. Starting from the public version of Gadget-2, we included the complex treatment of the baryon physics: gas cooling, star formation law, chemical evolution, and supernova feedback. We qualified the performances of GEAR in the case of dwarf spheroidal galaxies (dSphs) galaxies. Our code GEAR conserves the total energy budget of the systems to better than 5% over 14 Gyr and provides an excellent convergence of the results with numerical resolution. We showed that models of dSphs in a static Euclidean space, where the expansion of the universe is neglected are valid. In addition, we tackled some existing open questions in the field, such as the stellar mass fraction of dSphs and its link to the predicted dark matter halo mass function, the effect of supernova feedback, the spatial distribution of the stellar populations, and the origin of the diversity in star formation histories and chemical abundance patterns. Strong supernova-driven winds seem incompatible with the observed metallicities and luminosities. Despite newly formed stars being preferentially found in the galaxy central parts, turbulent motions in the gas can quickly erase any metallicity gradient. The diversity in properties of dSph are related to a range of total masses, as well as a range of dispersion in the central densities, which is also seen in the halos emerging from a Lambda CDM cosmogony.
DOI：
10.1086/590336
发表时间：
2008-05
期刊：
The Astrophysical Journal
影响因子：
--
作者：
N. Martin;J. D. de Jong;H. Rix
通讯作者：
N. Martin;J. D. de Jong;H. Rix